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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 |
---|---|---|---|---|---|---|---|---|---|
#626881 | #5148. Tree Distance | danielz | TL | 41ms | 63512kb | C++20 | 5.6kb | 2024-10-10 13:42:06 | 2024-10-10 13:42:08 |
Judging History
answer
#include "bits/stdc++.h"
using ll = long long;
const ll inf = 1e18;
using namespace std;
template <typename T>
void add(vector<T> &v, T x) { v.push_back(x); }
template <typename T, typename C>
void add(set<T, C> &v, T x) { v.insert(x); }
template <typename T>
void erase(vector<T> &v, T x) { v.erase(find(v.begin(), v.end(), x)); }
template <typename T, typename C>
void erase(set<T, C> &v, T x) { v.erase(x); }
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, class V = vector<T>>
struct Graph {
int n, m;
Graph() {}
Graph(int n, int m) : n(n), m(m) {}
V g[N];
void add(int u, T e) { ::add(g[u], 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;
::add(g[u], v);
if constexpr (is_same_v<T, W>) ::add(g[v], W{u, v.w});
else ::add(g[v], u);
}
return *this;
}
};
using namespace std;
template <int N, typename T = int>
struct ST {
static constexpr int K = 33 - __builtin_clz(N);
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 = log2(r - l);
return f(st[l][k], st[r - (1 << k)][k]);
}
};
template <int N, typename T = int, typename V = vector<T>>
struct Tree : Graph<N, T, V> {
int r, s[N], p[N];
ll d[N]{};
Tree() {}
Tree(int n) : Graph<N, T, V>(n, n - 1) {
fill(s, s + n + 1, 1);
}
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;
int 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);
}
int D(int u, int v) {
return d[u] + d[v] - 2 * d[lca(u, v)];
}
int cr, cp[N];
vector<int> cg[N];
int decompose(int x, int n) {
for (int y : this->g[x]) {
if (s[y] > n / 2) return decompose(y, n);
}
for(int y : this->g[x]) {
W e = *this->g[y].find(x);
this->g[y].erase(e);
add(cg[cp[y] = x], decompose(y, s[y]));
add(this->g[y], e);
}
return x;
}
Tree& decompose() { return cr = decompose(r, s[r]), *this; }
Tree& dfs() { return dfs(r), *this; }
Tree& input() { return Graph<N, T, V>::input(), *this; }
};
using namespace std;
template <int N, typename T>
struct Centroid {
Tree<N, T, set<T>> &t;
int r;
vector<int> g[N];
int decompose(int x, int n) {
for (auto y : t.g[x]) {
if (t.sz[y] > n / 2) return decompose(y, x, n);
}
for(int y : t.g[x]) {
t.g[y].erase(x);
g[x].push_back(decompose(y, x, t.sz[y]));
}
t.g[x].clear();
return x;
}
Centroid& decompose() {
return r = decompose(t.r, t.sz[t.r]), *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[N];
int main() {
int n; cin >> n;
Tree<N, W, set<W, less<>>> t(n);
t.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: 41ms
memory: 63512kb
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
Time Limit Exceeded
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...