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ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#629538 | #5148. Tree Distance | danielz | WA | 2547ms | 262068kb | C++20 | 5.0kb | 2024-10-11 13:01:59 | 2024-10-11 13:01:59 |
Judging History
answer
#include "bits/stdc++.h"
using ll = long long;
const ll inf = 1e18;
using namespace std;
struct W {
int v; ll w;
friend istream& operator>>(istream& is, W &e) { return is >> e.v >> e.w; }
friend ostream& operator<<(ostream& os, W &e) { return os << e.v << ":" << e.w; }
bool operator==(const W o) const { return make_pair(v, w) == make_pair(o.v, o.w); }
operator int() const { return v; }
bool operator<(const W &o) const { return make_pair(v, w) < make_pair(o.v, o.w); }
bool operator<(int x) const { return v < x; }
};
template <int N, typename T = int>
struct Graph {
int n, m;
Graph() {}
Graph(int n, int m) : n(n), m(m) {}
Graph& init(int n, int m) { return this->n = n, this->m = m, *this; }
vector<T> g[N];
void add(int u, T e) { g[u].push_back(e); }
void u(int u, int v) {
if constexpr (is_same_v<T, int>) {
add(u, v);
add(v, u);
}
}
Graph& input() {
for (int i = 0; i < m; i++) {
int u; T v; cin >> u >> v;
g[u].push_back(v);
if constexpr (is_same_v<T, W>) g[v].push_back({u, v.w});
else g[v].push_back(u);
}
return *this;
}
};
using namespace std;
constexpr int lg(int x) {
return 31 - __builtin_clz(x);
}
template <int N, typename T = int>
struct ST {
static constexpr int K = lg(N) + 1;
function<T(T, T)> f;
T st[N + 1][K]{};
void build(T a[N]) {
for (int i = 0; i < N; i++) st[i][0] = a[i];
for (int k = 1; k < K; k++) for (int i = 0; i < N; i++) {
st[i][k] = st[i][k - 1];
if (int j = i + (1 << (k - 1)); j < N) st[i][k] = f(st[i][k], st[j][k - 1]);
}
}
T F(int l, int r) {
assert(l < r);
int k = lg(r - l);
return f(st[l][k], st[r - (1 << k)][k]);
}
};
template <int N, typename T = int>
struct Tree : Graph<N, T> {
int r, s[N], p[N];
ll d[N]{};
Tree() {}
Tree& init(int n) {
Graph<N, T>::init(n, n - 1);
fill(s, s + n + 1, 1);
return *this;
}
Tree& root(int x) { return r = p[x] = x, *this; }
int I[N], o[2 * N]{}, t = 0;
ST<2 * N> st{[&](int x, int y) { return d[x] < d[y] ? x : y; }};
int dfs(int x) {
for (T e : this->g[x]) {
o[I[x] = t++] = x;
if (e == p[x]) continue;
ll w = 1;
if constexpr (is_same_v<T, W>) w = e.w;
d[e] = d[p[e] = x] + w;
s[x] += dfs(e);
}
if (x == r) st.build(o);
return s[x];
}
int lca(int u, int v) {
if (I[u] > I[v]) swap(u, v);
return st.F(I[u], I[v] + 1);
}
ll D(int u, int v) {
return d[u] + d[v] - 2 * d[lca(u, v)];
}
int cr, cp[N]{}, rem[N]{};
vector<int> cg[N];
int sz(int x, int p = -1) {
s[x] = 0;
for (int y : this->g[x]) if (!rem[y] && y != p) s[x] += sz(y, x);
return ++s[x];
}
int decompose(int x, int n, int p = -1) {
for (int y : this->g[x]) if (!rem[y] && y != p) {
if (s[y] > n / 2) return decompose(y, n, x);
}
rem[x] = true;
for(int y : this->g[x]) if (!rem[y]) {
y = decompose(y, sz(y));
cg[cp[y] = x].push_back(y);
}
return x;
}
Tree& decompose() { return cr = decompose(r, sz(r)), *this; }
Tree& dfs() { return dfs(r), *this; }
Tree& input() { return Graph<N, T>::input(), *this; }
};
using namespace std;
template <int N, typename T = int>
struct SGT {
T a[2 * N], t0;
function<T(T, T)> f;
SGT& fn(function<T(T, T)> f, T x) { return this->f = f, t0 = x, *this; }
SGT& fill(T x) { return ::fill(a, a + 2 * N, x), *this; }
T query(int l, int r) {
T tl = t0, tr = t0;
for (l += N, r += N; l < r; l >>= 1, r >>= 1) {
if (l & 1) tl = f(tl, a[l++]);
if (r & 1) tr = f(a[--r], tr);
}
return f(tl, tr);
}
void upd(int i, T x) {
for (a[i += N] = x; i >>= 1; ) a[i] = f(a[i << 1], a[i << 1|1]);
}
};
using namespace std;
const int N = 2e5 + 1;
struct P { int i; ll d;
bool operator<(const P &o) const { return i < o.i; }
};
struct E { int u, v; ll w;
bool operator<(const E &o) const {
return v == o.v ? w > o.w : v < o.v;
}
};
vector<P> v[N];
SGT<2 * N, ll> sgt;
ll r[10 * N];
Tree<N, W> t;
int main() {
int n; cin >> n;
t.init(n).input().root(1).dfs().decompose();
for (int i = 1; i <= n; i++) {
int j = i;
while (j) {
v[j].push_back({i, t.D(i, j)});
j = t.cp[j];
}
}
vector<E> e;
for (int i = 1; i <= n; i++) {
vector<P> st;
for (auto [j, d] : v[i]) {
while (st.size() && st.back().d >= d) {
e.push_back({st.back().i, j, t.D(st.back().i, j)});
st.pop_back();
}
if (st.size()) e.push_back({st.back().i, j, t.D(st.back().i, j)});
st.push_back({j, d});
}
}
sgt.fn([](ll x, ll y) { return min(x, y); }, inf).fill(inf);
int q; cin >> q;
for (int i = 0; i < q; i++) {
int u, v; cin >> u >> v;
e.push_back({u, v, -i});
}
sort(e.begin(), e.end());
for (auto [u, v, w] : e) {
if (w < 1) {
r[-w] = sgt.query(u, n + 1);
}
else sgt.upd(u, w);
}
for (int i = 0; i < q; i++) {
cout << (r[i] < inf ? r[i] : -1) << endl;
}
}
详细
Test #1:
score: 100
Accepted
time: 44ms
memory: 59568kb
input:
5 1 2 5 1 3 3 1 4 4 3 5 2 5 1 1 1 4 2 4 3 4 2 5
output:
-1 3 7 7 2
result:
ok 5 number(s): "-1 3 7 7 2"
Test #2:
score: -100
Wrong Answer
time: 2547ms
memory: 262068kb
input:
199999 31581 23211 322548833 176307 196803 690953895 34430 82902 340232856 36716 77480 466375266 7512 88480 197594480 95680 61864 679567992 19572 14126 599247796 188006 110716 817477802 160165 184035 722372640 23173 188594 490365246 54801 56250 304741654 10103 45884 643490340 127469 154479 214399361...
output:
29573323 1178569098929 4088 65959 9935 15508270844 760172089 4867978 328055210 55721881562 2062364707 339719 287433 287433 9935 138216269 8212187 9404444928 4453926 9935 710854 114886 65959 1818252547 92126 91087 9277701023 26776689 5718199 710854 92126 6129659427 365255209 92126 710854 287433 90165...
result:
wrong answer 5th numbers differ - expected: '4366', found: '9935'