#pragma region Macros
#ifdef noimi
#include "my_template.hpp"
#else
#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")

#include <immintrin.h>

#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <cctype>
#include <cfenv>
#include <cfloat>
#include <chrono>
#include <cinttypes>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdarg>
#include <cstddef>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <deque>
#include <fstream>
#include <functional>
#include <immintrin.h>
#include <initializer_list>
#include <iomanip>
#include <ios>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <streambuf>
#include <string>
#include <tuple>
#include <type_traits>
#include <utility>
#include <variant>

#ifdef noimi
#define oj_local(a, b) b
#else
#define oj_local(a, b) a
#endif

#define LOCAL if(oj_local(0, 1))
#define OJ if(oj_local(1, 0))

using namespace std;
using ll = long long;
using ull = unsigned long long int;
using i128 = __int128_t;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using ld = long double;
template <typename T> using vc = vector<T>;
template <typename T> using vvc = vector<vc<T>>;
template <typename T> using vvvc = vector<vvc<T>>;
using vi = vc<int>;
using vl = vc<ll>;
using vpi = vc<pii>;
using vpl = vc<pll>;
template <class T> using pq = priority_queue<T>;
template <class T> using pqg = priority_queue<T, vector<T>, greater<T>>;
template <typename T> int si(const T &x) { return x.size(); }
template <class T, class S> inline bool chmax(T &a, const S &b) { return (a < b ? a = b, 1 : 0); }
template <class T, class S> inline bool chmin(T &a, const S &b) { return (a > b ? a = b, 1 : 0); }
vi iota(int n) {
    vi a(n);
    return iota(a.begin(), a.end(), 0), a;
}
template <typename T> vi iota(const vector<T> &a, bool greater = false) {
    vi res(a.size());
    iota(res.begin(), res.end(), 0);
    sort(res.begin(), res.end(), [&](int i, int j) {
        if(greater) return a[i] > a[j];
        return a[i] < a[j];
    });
    return res;
}

// macros
#define overload5(a, b, c, d, e, name, ...) name
#define overload4(a, b, c, d, name, ...) name
#define endl '\n'
#define REP0(n) for(ll jidlsjf = 0; jidlsjf < n; ++jidlsjf)
#define REP1(i, n) for(ll i = 0; i < (n); ++i)
#define REP2(i, a, b) for(ll i = (a); i < (b); ++i)
#define REP3(i, a, b, c) for(ll i = (a); i < (b); i += (c))
#define rep(...) overload4(__VA_ARGS__, REP3, REP2, REP1, REP0)(__VA_ARGS__)
#define per0(n) for(int jidlsjf = 0; jidlsjf < (n); ++jidlsjf)
#define per1(i, n) for(ll i = (n)-1; i >= 0; --i)
#define per2(i, a, b) for(ll i = (a)-1; i >= b; --i)
#define per3(i, a, b, c) for(ll i = (a)-1; i >= (b); i -= (c))
#define per(...) overload4(__VA_ARGS__, per3, per2, per1, per0)(__VA_ARGS__)
#define fore0(a) rep(a.size())
#define fore1(i, a) for(auto &&i : a)
#define fore2(a, b, v) for(auto &&[a, b] : v)
#define fore3(a, b, c, v) for(auto &&[a, b, c] : v)
#define fore4(a, b, c, d, v) for(auto &&[a, b, c, d] : v)
#define fore(...) overload5(__VA_ARGS__, fore4, fore3, fore2, fore1, fore0)(__VA_ARGS__)
#define setbits(j, n) for(ll iiiii = (n), j = lowbit(iiiii); iiiii; iiiii ^= 1 << j, j = lowbit(iiiii))
#define perm(v) for(bool permrepflag = true; (permrepflag ? exchange(permrepflag, false) : next_permutation(all(v)));)
#define fi first
#define se second
#define pb push_back
#define ppb pop_back
#define ppf pop_front
#define eb emplace_back
#define drop(s) cout << #s << endl, exit(0)
#define si(c) (int)(c).size()
#define lb(c, x) distance((c).begin(), lower_bound(all(c), (x)))
#define lbg(c, x) distance((c).begin(), lower_bound(all(c), (x), greater{}))
#define ub(c, x) distance((c).begin(), upper_bound(all(c), (x)))
#define ubg(c, x) distance((c).begin(), upper_bound(all(c), (x), greater{}))
#define rng(v, l, r) v.begin() + (l), v.begin() + (r)
#define all(c) begin(c), end(c)
#define rall(c) rbegin(c), rend(c)
#define SORT(v) sort(all(v))
#define REV(v) reverse(all(v))
#define UNIQUE(x) SORT(x), x.erase(unique(all(x)), x.end())
template <typename T = ll, typename S> T SUM(const S &v) { return accumulate(all(v), T(0)); }
#define MIN(v) *min_element(all(v))
#define MAX(v) *max_element(all(v))
#define overload2(_1, _2, name, ...) name
#define vec(type, name, ...) vector<type> name(__VA_ARGS__)
#define vv(type, name, h, ...) vector<vector<type>> name(h, vector<type>(__VA_ARGS__))
#define vvv(type, name, h, w, ...) vector<vector<vector<type>>> name(h, vector<vector<type>>(w, vector<type>(__VA_ARGS__)))
#define vvvv(type, name, a, b, c, ...)                                                                                                                         \
    vector<vector<vector<vector<type>>>> name(a, vector<vector<vector<type>>>(b, vector<vector<type>>(c, vector<type>(__VA_ARGS__))))
constexpr pii dx4[4] = {pii{1, 0}, pii{0, 1}, pii{-1, 0}, pii{0, -1}};
constexpr pii dx8[8] = {{1, 0}, {1, 1}, {0, 1}, {-1, 1}, {-1, 0}, {-1, -1}, {0, -1}, {1, -1}};

namespace yesno_impl {
const string YESNO[2] = {"NO", "YES"};
const string YesNo[2] = {"No", "Yes"};
const string yesno[2] = {"no", "yes"};
const string firstsecond[2] = {"second", "first"};
const string FirstSecond[2] = {"Second", "First"};
const string possiblestr[2] = {"impossible", "possible"};
const string Possiblestr[2] = {"Impossible", "Possible"};
void YES(bool t = 1) { cout << YESNO[t] << endl; }
void NO(bool t = 1) { YES(!t); }
void Yes(bool t = 1) { cout << YesNo[t] << endl; }
void No(bool t = 1) { Yes(!t); }
void yes(bool t = 1) { cout << yesno[t] << endl; }
void no(bool t = 1) { yes(!t); }
void first(bool t = 1) { cout << firstsecond[t] << endl; }
void First(bool t = 1) { cout << FirstSecond[t] << endl; }
void possible(bool t = 1) { cout << possiblestr[t] << endl; }
void Possible(bool t = 1) { cout << Possiblestr[t] << endl; }
}; // namespace yesno_impl
using namespace yesno_impl;

#define INT(...)                                                                                                                                               \
    int __VA_ARGS__;                                                                                                                                           \
    IN(__VA_ARGS__)
#define INTd(...)                                                                                                                                              \
    int __VA_ARGS__;                                                                                                                                           \
    IN2(__VA_ARGS__)
#define LL(...)                                                                                                                                                \
    ll __VA_ARGS__;                                                                                                                                            \
    IN(__VA_ARGS__)
#define LLd(...)                                                                                                                                               \
    ll __VA_ARGS__;                                                                                                                                            \
    IN2(__VA_ARGS__)
#define STR(...)                                                                                                                                               \
    string __VA_ARGS__;                                                                                                                                        \
    IN(__VA_ARGS__)
#define CHR(...)                                                                                                                                               \
    char __VA_ARGS__;                                                                                                                                          \
    IN(__VA_ARGS__)
#define DBL(...)                                                                                                                                               \
    double __VA_ARGS__;                                                                                                                                        \
    IN(__VA_ARGS__)
#define VEC(type, name, size)                                                                                                                                  \
    vector<type> name(size);                                                                                                                                   \
    IN(name)
#define VECd(type, name, size)                                                                                                                                 \
    vector<type> name(size);                                                                                                                                   \
    IN2(name)
#define VEC2(type, name1, name2, size)                                                                                                                         \
    vector<type> name1(size), name2(size);                                                                                                                     \
    for(int i = 0; i < size; i++) IN(name1[i], name2[i])
#define VEC2d(type, name1, name2, size)                                                                                                                        \
    vector<type> name1(size), name2(size);                                                                                                                     \
    for(int i = 0; i < size; i++) IN2(name1[i], name2[i])
#define VEC3(type, name1, name2, name3, size)                                                                                                                  \
    vector<type> name1(size), name2(size), name3(size);                                                                                                        \
    for(int i = 0; i < size; i++) IN(name1[i], name2[i], name3[i])
#define VEC3d(type, name1, name2, name3, size)                                                                                                                 \
    vector<type> name1(size), name2(size), name3(size);                                                                                                        \
    for(int i = 0; i < size; i++) IN2(name1[i], name2[i], name3[i])
#define VEC4(type, name1, name2, name3, name4, size)                                                                                                           \
    vector<type> name1(size), name2(size), name3(size), name4(size);                                                                                           \
    for(int i = 0; i < size; i++) IN(name1[i], name2[i], name3[i], name4[i]);
#define VEC4d(type, name1, name2, name3, name4, size)                                                                                                          \
    vector<type> name1(size), name2(size), name3(size), name4(size);                                                                                           \
    for(int i = 0; i < size; i++) IN2(name1[i], name2[i], name3[i], name4[i]);
#define VV(type, name, h, w)                                                                                                                                   \
    vector<vector<type>> name(h, vector<type>(w));                                                                                                             \
    IN(name)
#define VVd(type, name, h, w)                                                                                                                                  \
    vector<vector<type>> name(h, vector<type>(w));                                                                                                             \
    IN2(name)
int scan() { return getchar(); }
void scan(int &a) { cin >> a; }
void scan(long long &a) { cin >> a; }
void scan(char &a) { cin >> a; }
void scan(double &a) { cin >> a; }
void scan(string &a) { cin >> a; }
template <class T, class S> void scan(pair<T, S> &p) { scan(p.first), scan(p.second); }
template <class T> void scan(vector<T> &);
template <class T> void scan(vector<T> &a) {
    for(auto &i : a) scan(i);
}
template <class T> void scan(T &a) { cin >> a; }
void IN() {}
void IN2() {}
template <class Head, class... Tail> void IN(Head &head, Tail &...tail) {
    scan(head);
    IN(tail...);
}
template <class Head, class... Tail> void IN2(Head &head, Tail &...tail) {
    scan(head);
    --head;
    IN2(tail...);
}

template <int p = -1> void pat() {}
template <int p = -1, class Head, class... Tail> void pat(Head &h, Tail &...tail) {
    h += p;
    pat<p>(tail...);
}

template <typename T, typename S> T ceil(T x, S y) {
    assert(y);
    return (y < 0 ? ceil(-x, -y) : (x > 0 ? (x + y - 1) / y : x / y));
}

template <typename T, typename S> T floor(T x, S y) {
    assert(y);
    return (y < 0 ? floor(-x, -y) : (x > 0 ? x / y : x / y - (x % y == 0 ? 0 : 1)));
}
template <typename T, typename S, typename U> U bigmul(const T &x, const S &y, const U &lim) { // clamp(x * y, -lim, lim)
    if(x < 0 and y < 0) return bigmul(-x, -y, lim);
    if(x < 0) return -bigmul(-x, y, lim);
    if(y < 0) return -bigmul(x, -y, lim);
    return y == 0 or x <= lim / y ? x * y : lim;
}
template <class T> T POW(T x, int n) {
    T res = 1;
    for(; n; n >>= 1, x *= x)
        if(n & 1) res *= x;
    return res;
}
template <class T, class S> T POW(T x, S n, const ll &mod) {
    T res = 1;
    x %= mod;
    for(; n; n >>= 1, x = x * x % mod)
        if(n & 1) res = res * x % mod;
    return res;
}
vector<pll> factor(ll x) {
    vector<pll> ans;
    for(ll i = 2; i * i <= x; i++)
        if(x % i == 0) {
            ans.push_back({i, 1});
            while((x /= i) % i == 0) ans.back().second++;
        }
    if(x != 1) ans.push_back({x, 1});
    return ans;
}
template <class T> vector<T> divisor(T x) {
    vector<T> ans;
    for(T i = 1; i * i <= x; i++)
        if(x % i == 0) {
            ans.pb(i);
            if(i * i != x) ans.pb(x / i);
        }
    return ans;
}
template <typename T> void zip(vector<T> &x) {
    vector<T> y = x;
    UNIQUE(y);
    for(int i = 0; i < x.size(); ++i) { x[i] = lb(y, x[i]); }
}
template <class S> void fold_in(vector<S> &v) {}
template <typename Head, typename... Tail, class S> void fold_in(vector<S> &v, Head &&a, Tail &&...tail) {
    for(auto e : a) v.emplace_back(e);
    fold_in(v, tail...);
}
template <class S> void renumber(vector<S> &v) {}
template <typename Head, typename... Tail, class S> void renumber(vector<S> &v, Head &&a, Tail &&...tail) {
    for(auto &&e : a) e = lb(v, e);
    renumber(v, tail...);
}
template <class S, class... Args> vector<S> zip(vector<S> &head, Args &&...args) {
    vector<S> v;
    fold_in(v, head, args...);
    sort(all(v)), v.erase(unique(all(v)), v.end());
    renumber(v, head, args...);
    return v;
}

template <typename S> void rearrange(const vector<S> &id) {}
template <typename S, typename T> void rearrange_exec(const vector<S> &id, vector<T> &v) {
    vector<T> w(v.size());
    rep(i, si(id)) w[i] = v[id[i]];
    v.swap(w);
}
// 並び替える順番, 並び替える vector 達
template <typename S, typename Head, typename... Tail> void rearrange(const vector<S> &id, Head &a, Tail &...tail) {
    rearrange_exec(id, a);
    rearrange(id, tail...);
}

template <typename T> vector<T> RUI(const vector<T> &v) {
    vector<T> res(v.size() + 1);
    for(int i = 0; i < v.size(); i++) res[i + 1] = res[i] + v[i];
    return res;
}
template <typename T> void zeta_supersetsum(vector<T> &f) {
    int n = f.size();
    for(int i = 1; i < n; i <<= 1) rep(b, n) if(!(i & b)) f[b] += f[b | i];
}

template <typename T> void zeta_subsetsum(vector<T> &f) {
    int n = f.size();
    for(int i = 1; i < n; i <<= 1) rep(b, n) if(!(i & b)) f[b | i] += f[b];
}
template <typename T> void mobius_subset(vector<T> &f) {
    int n = f.size();
    for(int i = 1; i < n; i <<= 1) rep(b, n) if(!(i & b)) f[b] -= f[b | i];
}
template <typename T> void mobius_superset(vector<T> &f) {
    int n = f.size();
    for(int i = 1; i < n; i <<= 1) rep(b, n) if(!(i & b)) f[b | i] -= f[b];
}
// 反時計周りに 90 度回転
template <typename T> void rot(vector<vector<T>> &v) {
    if(empty(v)) return;
    int n = v.size(), m = v[0].size();
    vector<vector<T>> res(m, vector<T>(n));
    rep(i, n) rep(j, m) res[m - 1 - j][i] = v[i][j];
    v.swap(res);
}

vector<int> counter(const vector<int> &v, int max_num = -1) {
    if(max_num == -1) max_num = MAX(v);
    vector<int> res(max_num + 1);
    fore(e, v) res[e]++;
    return res;
}

// x in [l, r)
template <class T, class S> bool inc(const T &x, const S &l, const S &r) { return l <= x and x < r; }
template <class T, class S> bool inc(const T &x, const pair<S, S> &p) { return p.first <= x and x < p.second; }

// 便利関数
constexpr ll ten(int n) { return n == 0 ? 1 : ten(n - 1) * 10; }
constexpr ll tri(ll n) { return n * (n + 1) / 2; }
// l + ... + r
constexpr ll tri(ll l, ll r) { return (l + r) * (r - l + 1) / 2; }
ll max(int x, ll y) { return max((ll)x, y); }
ll max(ll x, int y) { return max(x, (ll)y); }
int min(int x, ll y) { return min((ll)x, y); }
int min(ll x, int y) { return min(x, (ll)y); }
// bit 演算系
#define bit(i) (1LL << i)       // (1 << i)
#define test(b, i) (b >> i & 1) // b の i bit 目が立っているか
ll pow2(int i) { return 1LL << i; }
int topbit(signed t) { return t == 0 ? -1 : 31 - __builtin_clz(t); }
int topbit(ll t) { return t == 0 ? -1 : 63 - __builtin_clzll(t); }
int lowbit(signed a) { return a == 0 ? 32 : __builtin_ctz(a); }
int lowbit(ll a) { return a == 0 ? 64 : __builtin_ctzll(a); }
// int allbit(int n) { return (1 << n) - 1; }
constexpr ll mask(int n) { return (1LL << n) - 1; }
// int popcount(signed t) { return __builtin_popcount(t); }
// int popcount(ll t) { return __builtin_popcountll(t); }
int popcount(uint64_t t) { return __builtin_popcountll(t); }
static inline uint64_t popcount64(uint64_t x) {
    uint64_t m1 = 0x5555555555555555ll;
    uint64_t m2 = 0x3333333333333333ll;
    uint64_t m4 = 0x0F0F0F0F0F0F0F0Fll;
    uint64_t h01 = 0x0101010101010101ll;

    x -= (x >> 1) & m1;
    x = (x & m2) + ((x >> 2) & m2);
    x = (x + (x >> 4)) & m4;

    return (x * h01) >> 56;
}
bool ispow2(int i) { return i && (i & -i) == i; }

ll rnd(ll l, ll r) { //[l, r)
#ifdef noimi
    static mt19937_64 gen;
#else
    static mt19937_64 gen(chrono::steady_clock::now().time_since_epoch().count());
#endif
    return uniform_int_distribution<ll>(l, r - 1)(gen);
}
ll rnd(ll n) { return rnd(0, n); }

template <class t> void random_shuffle(vc<t> &a) { rep(i, si(a)) swap(a[i], a[rnd(0, i + 1)]); }

int in() {
    int x;
    cin >> x;
    return x;
}
ll lin() {
    unsigned long long x;
    cin >> x;
    return x;
}

template <class T, class S> pair<T, S> operator-(const pair<T, S> &x) { return pair<T, S>(-x.first, -x.second); }
template <class T, class S> pair<T, S> operator-(const pair<T, S> &x, const pair<T, S> &y) { return pair<T, S>(x.fi - y.fi, x.se - y.se); }
template <class T, class S> pair<T, S> operator+(const pair<T, S> &x, const pair<T, S> &y) { return pair<T, S>(x.fi + y.fi, x.se + y.se); }
template <class T> pair<T, T> operator&(const pair<T, T> &l, const pair<T, T> &r) { return pair<T, T>(max(l.fi, r.fi), min(l.se, r.se)); }
template <class T, class S> pair<T, S> operator+=(pair<T, S> &l, const pair<T, S> &r) { return l = l + r; }
template <class T, class S> pair<T, S> operator-=(pair<T, S> &l, const pair<T, S> &r) { return l = l - r; }
template <class T> bool intersect(const pair<T, T> &l, const pair<T, T> &r) { return (l.se < r.se ? r.fi < l.se : l.fi < r.se); }

template <class T> vector<T> &operator++(vector<T> &v) {
    fore(e, v) e++;
    return v;
}
template <class T> vector<T> operator++(vector<T> &v, int) {
    auto res = v;
    fore(e, v) e++;
    return res;
}
template <class T> vector<T> &operator--(vector<T> &v) {
    fore(e, v) e--;
    return v;
}
template <class T> vector<T> operator--(vector<T> &v, int) {
    auto res = v;
    fore(e, v) e--;
    return res;
}
template <class T> void connect(vector<T> &l, const vector<T> &r) { fore(e, r) l.eb(e); }
template <class T> vector<T> operator+(const vector<T> &l, const vector<T> &r) {
    vector<T> res(max(si(l), si(r)));
    rep(i, si(l)) res[i] += l[i];
    rep(i, si(r)) res[i] += r[i];
    return res;
}
template <class T> vector<T> operator-(const vector<T> &l, const vector<T> &r) {
    vector<T> res(max(si(l), si(r)));
    rep(i, si(l)) res[i] += l[i];
    rep(i, si(r)) res[i] -= r[i];
    return res;
}
template <class T> vector<T> &operator+=(const vector<T> &l, const vector<T> &r) {
    if(si(l) < si(r)) l.resize(si(r));
    rep(i, si(r)) l[i] += r[i];
    return l;
}
template <class T> vector<T> &operator-=(const vector<T> &l, const vector<T> &r) {
    if(si(l) < si(r)) l.resize(si(r));
    rep(i, si(r)) l[i] -= r[i];
    return l;
}
template <class T> vector<T> &operator+=(vector<T> &v, const T &x) {
    fore(e, v) e += x;
    return v;
}
template <class T> vector<T> &operator-=(vector<T> &v, const T &x) {
    fore(e, v) e -= x;
    return v;
}

template <typename T> struct edge {
    int from, to;
    T cost;
    int id;
    edge(int to, T cost) : from(-1), to(to), cost(cost) {}
    edge(int from, int to, T cost) : from(from), to(to), cost(cost) {}
    edge(int from, int to, T cost, int id) : from(from), to(to), cost(cost), id(id) {}
    constexpr bool operator<(const edge<T> &rhs) const noexcept { return cost < rhs.cost; }
    edge &operator=(const int &x) {
        to = x;
        return *this;
    }
    operator int() const { return to; }
    friend ostream operator<<(ostream &os, const edge &e) { return os << e.to; }
};
template <typename T> using Edges = vector<edge<T>>;

template <typename T = int> Edges<T> read_edges(int m, bool weighted = false) {
    Edges<T> res;
    res.reserve(m);
    for(int i = 0; i < m; i++) {
        int u, v, c = 0;
        scan(u), scan(v), u--, v--;
        if(weighted) scan(c);
        res.eb(u, v, c, i);
    }
    return res;
}

using Tree = vector<vector<int>>;
using Graph = vector<vector<int>>;
template <class T> using Wgraph = vector<vector<edge<T>>>;
Graph getG(int n, int m = -1, bool directed = false, int margin = 1) {
    Tree res(n);
    if(m == -1) m = n - 1;
    while(m--) {
        int a, b;
        cin >> a >> b;
        a -= margin, b -= margin;
        res[a].emplace_back(b);
        if(!directed) res[b].emplace_back(a);
    }
    return res;
}
Graph getTreeFromPar(int n, int margin = 1) {
    Graph res(n);
    for(int i = 1; i < n; i++) {
        int a;
        cin >> a;
        res[a - margin].emplace_back(i);
    }
    return res;
}
template <class T> Wgraph<T> getWg(int n, int m = -1, bool directed = false, int margin = 1) {
    Wgraph<T> res(n);
    if(m == -1) m = n - 1;
    while(m--) {
        int a, b;
        T c;
        scan(a), scan(b), scan(c);
        a -= margin, b -= margin;
        res[a].emplace_back(b, c);
        if(!directed) res[b].emplace_back(a, c);
    }
    return res;
}
void add(Graph &G, int x, int y) { G[x].eb(y), G[y].eb(x); }
template <class S, class T> void add(Wgraph<S> &G, int x, int y, T c) { G[x].eb(y, c), G[y].eb(x, c); }

#define TEST                                                                                                                                                   \
    INT(testcases);                                                                                                                                            \
    while(testcases--)

i128 abs(const i128 &x) { return x > 0 ? x : -x; }
istream &operator>>(istream &is, i128 &v) {
    string s;
    is >> s;
    v = 0;
    for(int i = 0; i < (int)s.size(); i++) {
        if(isdigit(s[i])) { v = v * 10 + s[i] - '0'; }
    }
    if(s[0] == '-') { v *= -1; }
    return is;
}

ostream &operator<<(ostream &os, const i128 &v) {
    if(v == 0) { return (os << "0"); }
    i128 num = v;
    if(v < 0) {
        os << '-';
        num = -num;
    }
    string s;
    for(; num > 0; num /= 10) { s.push_back((char)(num % 10) + '0'); }
    reverse(s.begin(), s.end());
    return (os << s);
}
namespace aux {
template <typename T, unsigned N, unsigned L> struct tp {
    static void output(std::ostream &os, const T &v) {
        os << std::get<N>(v) << (&os == &cerr ? ", " : " ");
        tp<T, N + 1, L>::output(os, v);
    }
};
template <typename T, unsigned N> struct tp<T, N, N> {
    static void output(std::ostream &os, const T &v) { os << std::get<N>(v); }
};
} // namespace aux
template <typename... Ts> std::ostream &operator<<(std::ostream &os, const std::tuple<Ts...> &t) {
    if(&os == &cerr) { os << '('; }
    aux::tp<std::tuple<Ts...>, 0, sizeof...(Ts) - 1>::output(os, t);
    if(&os == &cerr) { os << ')'; }
    return os;
}
template <typename T, typename S, typename U> std::ostream &operator<<(std::ostream &os, const priority_queue<T, S, U> &_pq) {
    auto pq = _pq;
    vector<T> res;
    while(!empty(pq)) res.emplace_back(pq.top()), pq.pop();
    return os << res;
}
template <class T, class S> ostream &operator<<(ostream &os, const pair<T, S> &p) {
    if(&os == &cerr) { return os << "(" << p.first << ", " << p.second << ")"; }
    return os << p.first << " " << p.second;
}
template <class Ch, class Tr, class Container> std::basic_ostream<Ch, Tr> &operator<<(std::basic_ostream<Ch, Tr> &os, const Container &x) {
    bool f = true;
    if(&os == &cerr) os << "[";
    for(auto &y : x) {
        if(&os == &cerr)
            os << (f ? "" : ", ") << y;
        else
            os << (f ? "" : " ") << y;
        f = false;
    }
    if(&os == &cerr) os << "]";
    return os;
}

#define dump(...) static_cast<void>(0)
#define dbg(...) static_cast<void>(0)

void OUT() { cout << endl; }
template <class Head, class... Tail> void OUT(const Head &head, const Tail &...tail) {
    cout << head;
    if(sizeof...(tail)) cout << ' ';
    OUT(tail...);
}

template <typename T> static constexpr T inf = numeric_limits<T>::max() / 2;
template <class T, class S> constexpr pair<T, S> inf<pair<T, S>> = {inf<T>, inf<S>};

template <class T> void OUT2(const T &t, T INF = inf<T>, T res = -1) { OUT(t != INF ? t : res); }
template <class T> void OUT2(vector<T> &v, T INF = inf<T>, T res = -1) {
    fore(e, v) if(e == INF) e = res;
    OUT(v);
    fore(e, v) if(e == res) e = INF;
}

template <class F> struct REC {
    F f;
    REC(F &&f_) : f(forward<F>(f_)) {}
    template <class... Args> auto operator()(Args &&...args) const { return f(*this, forward<Args>(args)...); }
};

template <class S> vector<pair<S, int>> runLength(const vector<S> &v) {
    vector<pair<S, int>> res;
    for(auto &e : v) {
        if(res.empty() or res.back().fi != e)
            res.eb(e, 1);
        else
            res.back().se++;
    }
    return res;
}
vector<pair<char, int>> runLength(const string &v) {
    vector<pair<char, int>> res;
    for(auto &e : v) {
        if(res.empty() or res.back().fi != e)
            res.eb(e, 1);
        else
            res.back().se++;
    }
    return res;
}

struct string_converter {
    char start = 0;
    char type(const char &c) const { return (islower(c) ? 'a' : isupper(c) ? 'A' : isdigit(c) ? '0' : 0); }
    int convert(const char &c) {
        if(!start) start = type(c);
        return c - start;
    }
    int convert(const char &c, const string &chars) { return chars.find(c); }
    template <typename T> auto convert(const T &v) {
        vector<decltype(convert(v[0]))> ret;
        ret.reserve(size(v));
        for(auto &&e : v) ret.emplace_back(convert(e));
        return ret;
    }
    template <typename T> auto convert(const T &v, const string &chars) {
        vector<decltype(convert(v[0], chars))> ret;
        ret.reserve(size(v));
        for(auto &&e : v) ret.emplace_back(convert(e, chars));
        return ret;
    }
    int operator()(const char &v, char s = 0) {
        start = s;
        return convert(v);
    }
    int operator()(const char &v, const string &chars) { return convert(v, chars); }
    template <typename T> auto operator()(const T &v, char s = 0) {
        start = s;
        return convert(v);
    }
    template <typename T> auto operator()(const T &v, const string &chars) { return convert(v, chars); }
} toint;

template <class T, class F> T bin_search(T ok, T ng, const F &f) {
    while(abs(ok - ng) > 1) {
        T mid = ok + ng >> 1;
        (f(mid) ? ok : ng) = mid;
    }
    return ok;
}
template <class T, class F> T bin_search_double(T ok, T ng, const F &f, int iter = 80) {
    while(iter--) {
        // T mid = (ok + ng) / 2;
        T mid = sqrtl(ok * ng);
        (f(mid) ? ok : ng) = mid;
    }
    return ok;
}

struct Setup_io {
    Setup_io() {
        ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
        cout << fixed << setprecision(11);
    }
} setup_io;

#endif

#pragma endregion

namespace fast_gcd {
using u64 = uint64_t;
using u32 = uint32_t;

__attribute__((target("bmi"))) constexpr u64 binary_gcd(u64 a, u64 b) {
    if(a == 0 || b == 0) return a + b;
    int n = __builtin_ctzll(a);
    int m = __builtin_ctzll(b);
    a >>= n;
    b >>= m;
    while(a != b) {
        int m = __builtin_ctzll(a - b);
        bool f = a > b;
        u64 c = f ? a : b;
        b = f ? b : a;
        a = (c - b) >> m;
    }
    return a << min(n, m);
}
} // namespace fast_gcd

using fast_gcd::binary_gcd;
// q / p
struct frac {
    template <typename T> static constexpr inline T gcd(const T a, const T b) { return (b == 0) ? a : gcd(b, a % b); }
    ll q, p;
    inline constexpr void simplify() {
        if(p < 0) {
            p *= -1;
            q *= -1;
        }
        ll g = binary_gcd(q < 0 ? -q : q, p);
        if(g) {
            p /= g;
            q /= g;
            if(p == 0 and q < 0) q = 1;
        }
    }
    constexpr frac(ll q = 0, ll p = 1) noexcept : q(q), p(p) { simplify(); }

    constexpr bool operator<(const frac &r) const { return q * r.p < p * r.q; }
    constexpr bool operator>(const frac &r) const { return q * r.p > p * r.q; }
    constexpr bool operator<=(const frac &r) const { return q * r.p <= p * r.q; }
    constexpr bool operator>=(const frac &r) const { return q * r.p >= p * r.q; }
    template <class T> constexpr bool operator<(const T &r) const { return *this < frac(r); }
    template <class T> constexpr bool operator>(const T &r) const { return *this > frac(r); }
    constexpr bool operator==(const frac &r) const { return q * r.p == p * r.q; }
    constexpr bool operator!=(const frac &r) const { return !((*this) == r); }
    constexpr frac operator+() const noexcept { return *this; }
    constexpr frac operator-() const noexcept { return frac(-q, p); }
    constexpr frac operator+(const frac r) const noexcept { return frac(*this) += r; }
    constexpr frac operator-(const frac r) const noexcept { return frac(*this) -= r; }
    constexpr frac operator*(const frac r) const noexcept { return frac(*this) *= r; }
    constexpr frac operator/(const frac r) const noexcept { return frac(*this) /= r; }
    constexpr frac &operator+=(const frac &r) noexcept {
        ll g = binary_gcd(p, r.p);
        q = r.p / g * q + p / g * r.q;
        p = p / g * r.p;
        (*this).simplify();
        return *this;
    }
    constexpr frac &operator-=(const frac &r) noexcept {
        ll g = binary_gcd(p, r.p);
        q = r.p / g * q - p / g * r.q;
        p = p / g * r.p;
        (*this).simplify();
        return *this;
    }
    constexpr frac &operator*=(const frac &r) noexcept {
        q *= r.q;
        p *= r.p;
        (*this).simplify();
        return *this;
    }
    constexpr frac &operator/=(const frac &r) noexcept {
        q *= r.p;
        p *= r.q;
        (*this).simplify();
        return *this;
    }

    void print() {
        long double tmp = (long double)q / (long double)p;
        cout << tmp;
    }
};
istream &operator>>(istream &is, frac &p) {
    ll a;
    is >> a;
    p = frac(a, 1);
    return is;
}
ostream &operator<<(ostream &os, const frac &r) { return os << 1.0 * r.q / r.p; }

namespace Geometry {
using T = long double;
constexpr T eps = 1e-9;

bool eq(const T &x, const T &y) { return abs(x - y) <= eps; }
inline constexpr int type(T x, T y) {
    if(x == 0 and y == 0) return 0;
    if(y < 0 or (y == 0 and x > 0)) return -1;
    return 1;
}
struct Point {
    T x, y;
    constexpr Point(T _x = 0, T _y = 0) : x(_x), y(_y) {}
    constexpr Point operator+() const noexcept { return *this; }
    constexpr Point operator-() const noexcept { return Point(-x, -y); }
    constexpr Point operator+(const Point &p) const { return Point(x + p.x, y + p.y); }
    constexpr Point operator-(const Point &p) const { return Point(x - p.x, y - p.y); }
    constexpr Point &operator+=(const Point &p) { return x += p.x, y += p.y, *this; }
    constexpr Point &operator-=(const Point &p) { return x -= p.x, y -= p.y, *this; }
    constexpr T operator*(const Point &p) const { return x * p.x + y * p.y; }
    constexpr Point &operator*=(const T &k) { return x *= k, y *= k, *this; }
    constexpr Point operator*(const T &k) { return Point(x * k, y * k); }
    constexpr bool operator==(const Point &r) const noexcept { return r.x == x and r.y == y; }
    constexpr T cross(const Point &r) const { return x * r.y - y * r.x; }

    constexpr bool operator<(const Point &r) const { return pair(x, y) < pair(r.x, r.y); }

    // 1 : left, 0 : same, -1 : right
    constexpr int toleft(const Point &r) const {
        auto t = cross(r);
        return t > eps ? 1 : t < -eps ? -1 : 0;
    }

    constexpr bool arg_cmp(const Point &r) const {
        int L = type(x, y), R = type(r.x, r.y);
        if(L != R) return L < R;

        T X = x * r.y, Y = r.x * y;
        if(X != Y) return X > Y;
        return x < r.x;
    }
};
bool arg_cmp(const Point &l, const Point &r) { return l.arg_cmp(r); }
ostream &operator<<(ostream &os, const Point &p) { return os << p.x << " " << p.y; }
istream &operator>>(istream &is, Point &p) {
    is >> p.x >> p.y;
    return is;
}

struct Line {
    Point a, b;
    Line() = default;
    Line(Point a, Point b) : a(a), b(b) {}
    // ax + by = c
    Line(T A, T B, T C) {
        if(A == 0) {
            a = Point(0, C / B), b = Point(1, C / B);
        } else if(B == 0) {
            a = Point(C / A, 0), b = Point(C / A, 1);
        } else {
            a = Point(0, C / B), b = Point(C / A, 0);
        }
    }
    // 1 : left, 0 : same, -1 : right
    constexpr int toleft(const Point &r) const {
        auto t = (b - a).cross(r - a);
        return t > eps ? 1 : t < -eps ? -1 : 0;
    }

    friend std::ostream &operator<<(std::ostream &os, Line &ls) {
        return os << "{"
                  << "(" << ls.a.x << ", " << ls.a.y << "), (" << ls.b.x << ", " << ls.b.y << ")}";
    }
};
istream &operator>>(istream &is, Line &p) { return is >> p.a >> p.b; }
Point rotate(long double theta, const Point &p) { return Point(cosl(theta) * p.x - sinl(theta) * p.y, sinl(theta) * p.x + cosl(theta) * p.y); }

struct Segment : Line {
    Segment() = default;
    Segment(Point a, Point b) : Line(a, b) {}
};

ostream &operator<<(ostream &os, Segment &p) { return os << p.a << " to " << p.b; }
istream &operator>>(istream &is, Segment &p) {
    is >> p.a >> p.b;
    return is;
}

struct Circle {
    Point p;
    T r;
    Circle() = default;
    Circle(Point p, T r) : p(p), r(r) {}
};

using pt = Point;
using Points = vector<pt>;
using Polygon = Points;
T cross(const pt &x, const pt &y) { return x.x * y.y - x.y * y.x; }
T dot(const pt &x, const pt &y) { return x.x * y.x + x.y * y.y; }

T abs2(const pt &x) { return dot(x, x); }
// http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_1_C
// 点の回転方向
int ccw(const Point &a, Point b, Point c) {
    b = b - a, c = c - a;
    if(cross(b, c) > 0) return +1;   // "COUNTER_CLOCKWISE"
    if(cross(b, c) < 0) return -1;   // "CLOCKWISE"
    if(dot(b, c) < 0) return +2;     // "ONLINE_BACK"
    if(abs2(b) < abs2(c)) return -2; // "ONLINE_FRONT"
    return 0;                        // "ON_SEGMENT"
}

// http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_2_A
// 平行判定
bool parallel(const Line &a, const Line &b) { return (cross(a.b - a.a, b.b - b.a) == 0); }

// http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_2_A
// 垂直判定
bool orthogonal(const Line &a, const Line &b) { return (dot(a.a - a.b, b.a - b.b) == 0); }

bool intersect(const Line &l, const Point &p) { return abs(ccw(l.a, l.b, p)) != 1; }

bool intersect(const Line &l, const Line &m) { return !parallel(l, m); }

bool intersect(const Segment &s, const Point &p) { return ccw(s.a, s.b, p) == 0; }

bool intersect(const Line &l, const Segment &s) { return cross(l.b - l.a, s.a - l.a) * cross(l.b - l.a, s.b - l.a) <= 0; }

// http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_2_B
bool intersect(const Segment &s, const Segment &t) { return ccw(s.a, s.b, t.a) * ccw(s.a, s.b, t.b) <= 0 && ccw(t.a, t.b, s.a) * ccw(t.a, t.b, s.b) <= 0; }

bool intersect(const Polygon &ps, const Polygon &qs) {
    int pl = si(ps), ql = si(qs), i = 0, j = 0;
    while((i < pl or j < ql) and (i < 2 * pl) and (j < 2 * ql)) {
        auto ps0 = ps[(i + pl - 1) % pl], ps1 = ps[i % pl];
        auto qs0 = qs[(j + ql - 1) % ql], qs1 = qs[j % ql];
        if(intersect(Segment(ps0, ps1), Segment(qs0, qs1))) return true;
        Point a = ps1 - ps0;
        Point b = qs1 - qs0;
        T v = cross(a, b);
        T va = cross(qs1 - qs0, ps1 - qs0);
        T vb = cross(ps1 - ps0, qs1 - ps0);

        if(!v and va < 0 and vb < 0) return false;
        if(!v and !va and !vb) {
            i += 1;
        } else if(v >= 0) {
            if(vb > 0)
                i += 1;
            else
                j += 1;
        } else {
            if(va > 0)
                j += 1;
            else
                i += 1;
        }
    }
    return false;
}

T norm(const Point &p) { return p.x * p.x + p.y * p.y; }
Point projection(const Segment &l, const Point &p) {
    T t = dot(p - l.a, l.a - l.b) / norm(l.a - l.b);
    return l.a + (l.a - l.b) * t;
}

Point crosspoint(const Line &l, const Line &m) {
    T A = cross(l.b - l.a, m.b - m.a);
    T B = cross(l.b - l.a, l.b - m.a);
    if(A == 0 and B == 0) return m.a;
    return m.a + (m.b - m.a) * (B / A);
}

// http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_2_C
Point crosspoint(const Segment &l, const Segment &m) { return crosspoint(Line(l), Line(m)); }

// http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_3_B
// 凸性判定
bool is_convex(const Points &p) {
    int n = (int)p.size();
    for(int i = 0; i < n; i++) {
        if(ccw(p[(i + n - 1) % n], p[i], p[(i + 1) % n]) == -1) return false;
    }
    return true;
}

Points convex_hull(Points p) {
    int n = p.size(), k = 0;
    if(n <= 2) return p;
    sort(begin(p), end(p), [](pt x, pt y) { return (x.x != y.x ? x.x < y.x : x.y < y.y); });
    Points ch(2 * n);
    for(int i = 0; i < n; ch[k++] = p[i++]) {
        while(k >= 2 && cross(ch[k - 1] - ch[k - 2], p[i] - ch[k - 1]) <= 0) --k;
    }
    for(int i = n - 2, t = k + 1; i >= 0; ch[k++] = p[i--]) {
        while(k >= t && cross(ch[k - 1] - ch[k - 2], p[i] - ch[k - 1]) <= 0) --k;
    }
    ch.resize(k - 1);
    return ch;
}

// 面積の 2 倍
T area2(const Points &p) {
    T res = 0;
    rep(i, si(p)) { res += cross(p[i], p[i == si(p) - 1 ? 0 : i + 1]); }
    return res;
}

enum { _OUT, _ON, _IN };

int contains(const Polygon &Q, const Point &p) {
    bool in = false;
    for(int i = 0; i < Q.size(); i++) {
        Point a = Q[i] - p, b = Q[(i + 1) % Q.size()] - p;
        if(a.y > b.y) swap(a, b);
        if(a.y <= 0 && 0 < b.y && cross(a, b) < 0) in = !in;
        if(cross(a, b) == 0 && dot(a, b) <= 0) return _ON;
    }
    return in ? _IN : _OUT;
}

Polygon Minkowski_sum(const Polygon &P, const Polygon &Q) {
    vector<Segment> e1(P.size()), e2(Q.size()), ed(P.size() + Q.size());
    const auto cmp = [](const Segment &u, const Segment &v) { return (u.b - u.a).arg_cmp(v.b - v.a); };
    rep(i, P.size()) e1[i] = {P[i], P[(i + 1) % P.size()]};
    rep(i, Q.size()) e2[i] = {Q[i], Q[(i + 1) % Q.size()]};
    rotate(begin(e1), min_element(all(e1), cmp), end(e1));
    rotate(begin(e2), min_element(all(e2), cmp), end(e2));
    merge(all(e1), all(e2), begin(ed), cmp);
    const auto check = [](const Points &res, const Point &u) {
        const auto back1 = res.back(), back2 = *prev(end(res), 2);
        return eq(cross(back1 - back2, u - back2), eps) and dot(back1 - back2, u - back1) >= -eps;
    };
    auto u = e1[0].a + e2[0].a;
    Points res{u};
    res.reserve(P.size() + Q.size());
    for(const auto &v : ed) {
        u = u + v.b - v.a;
        while(si(res) >= 2 and check(res, u)) res.pop_back();
        res.eb(u);
    }
    if(res.size() and check(res, res[0])) res.pop_back();
    return res;
}

// -1 : on, 0 : out, 1 : in
// O(log(n))
int is_in(const Polygon &p, const Point &a) {
    if(p.size() == 1) return a == p[0] ? -1 : 0;
    if(p.size() == 2) return intersect(Segment(p[0], p[1]), a);
    if(a == p[0]) return -1;
    if((p[1] - p[0]).toleft(a - p[0]) == -1 || (p.back() - p[0]).toleft(a - p[0]) == 1) return 0;
    const auto cmp = [&](const Point &u, const Point &v) { return (u - p[0]).toleft(v - p[0]) == 1; };
    const size_t i = lower_bound(p.begin() + 1, p.end(), a, cmp) - p.begin();
    if(i == 1) return intersect(Segment(p[0], p[i]), a) ? -1 : 0;
    if(i == p.size() - 1 && intersect(Segment(p[0], p[i]), a)) return -1;
    if(intersect(Segment(p[i - 1], p[i]), a)) return -1;
    return (p[i] - p[i - 1]).toleft(a - p[i - 1]) > 0;
}

Points halfplane_intersection(vector<Line> L, const T inf = 1e9) {
    Point box[4] = {Point(inf, inf), Point(-inf, inf), Point(-inf, -inf), Point(inf, -inf)};
    rep(i, 4) { L.emplace_back(box[i], box[(i + 1) % 4]); }
    sort(all(L), [](const Line &l, const Line &r) { return (l.b - l.a).arg_cmp(r.b - r.a); });
    deque<Line> dq;
    int len = 0;
    auto check = [](const Line &a, const Line &b, const Line &c) { return a.toleft(crosspoint(b, c)) == -1; };
    rep(i, L.size()) {
        while(dq.size() > 1 and check(L[i], *(end(dq) - 2), *(end(dq) - 1))) dq.pop_back();
        while(dq.size() > 1 and check(L[i], dq[0], dq[1])) dq.pop_front();
        // dump(L[i], si(dq));

        if(dq.size() and eq(cross(L[i].b - L[i].a, dq.back().b - dq.back().a), 0)) {
            if(dot(L[i].b - L[i].a, dq.back().b - dq.back().a) < eps) return {};
            if(L[i].toleft(dq.back().a) == -1)
                dq.pop_back();
            else
                continue;
        }
        dq.emplace_back(L[i]);
    }

    while(dq.size() > 2 and check(dq[0], *(end(dq) - 2), *(end(dq) - 1))) dq.pop_back();
    while(dq.size() > 2 and check(dq.back(), dq[0], dq[1])) dq.pop_front();
    if(si(dq) < 3) return {};
    Polygon ret(dq.size());
    rep(i, dq.size()) ret[i] = crosspoint(dq[i], dq[(i + 1) % dq.size()]);
    Polygon res;
    fore(e, ret) {
        if(empty(res) or !(res.back() == e)) res.eb(e);
    }
    while(si(res) > 1 and res.front() == res.back()) res.pop_back();
    return res;
}
} // namespace Geometry

using namespace Geometry;
Point projection(const Line &l, const Point &p) {
    long double t = dot(p - l.a, l.a - l.b) / norm(l.a - l.b);
    return l.a + (l.a - l.b) * t;
}

Point projection(const Segment &l, const Point &p) {
    long double t = dot(p - l.a, l.a - l.b) / norm(l.a - l.b);
    return l.a + (l.a - l.b) * t;
}
long double abs(Point P) { return sqrtl(abs2(P)); }

long double dist(const Point &A, const Point &B) { return hypot(A.x - B.x, A.y - B.y); }
// 三角形 PAB の内部の点の、P との距離の二乗の期待値
long double solve(const Point &P, const Point &A, const Point &B) {
    if(dist(A, B) < 1e-11) {
        Point C = (A + B) * 0.5;
        return ((P.x - C.x) * (P.x - C.x) + (P.y - C.y) * (P.y - C.y)) / 3;
    }
    auto H = projection(Line(A, B), P);
    long double h = abs(H - P), a = abs(H - A), b = abs(H - B);
    if(ccw(A, H, B) == -2) a = -a;
    return (a * a + a * b + b * b + h * h * 3) / 6;
}

const long double PI = acosl(-1);

int main() {
    INT(xl, yl, xr, yr);
    INT(n);
    Points P(n);
    rep(i, n) { cin >> P[i].x >> P[i].y; }

    vector<Line> rect;
    rect.eb(Line(Point(xl, yl), Point(xr, yl)));
    rect.eb(Line(Point(xr, yl), Point(xr, yr)));
    rect.eb(Line(Point(xr, yr), Point(xl, yr)));
    rect.eb(Line(Point(xl, yr), Point(xl, yl)));

    long double ans = 0;
    rep(i, n) {
        auto v = rect, w = rect;
        // v : min, w : max
        rep(j, n) {
            dump(i, j);
            if(i == j) continue;
            Point mid = (P[i] + P[j]) * 0.5;
            Point nxt = mid + rotate(PI / 2, mid - P[i]);
            v.eb(Line(mid, nxt));
            w.eb(Line(nxt, mid));
        }
        dump(i);
        auto f = [&](vector<Line> &v) {
            auto C = halfplane_intersection(v);
            dump(C);
            long double res = 0;
            rep(j, si(C)) {
                auto p = C[j], q = C[(j + 1) % si(C)];
                auto F1 = [&](Point p) { return -powl(p.y - P[i].y, 3) / 3; };
                auto F2 = [&](Point p) { return powl(p.x - P[i].x, 3) / 3; };

                auto p0 = p;
                auto p1 = (p * 2 + q) * (1. / 3);
                auto p2 = (p + q * 2) * (1. / 3);
                auto p3 = q;
                res += (q.x - p.x) * (F1(p0) + F1(p1) * 3 + F1(p2) * 3 + F1(p3)) / 8;
                res += (q.y - p.y) * (F2(p0) + F2(p1) * 3 + F2(p2) * 3 + F2(p3)) / 8;
            }
            dump(res);
            return res;
        };
        ans += f(w) - f(v);
    }
    OUT(ans / (xr - xl) / (yr - yl) * PI);
}