#ifndef hwe
#include "race.h"
#endif
#include <bits/stdc++.h>
using namespace std;
#define popcount(n) (__builtin_popcountll((n)))
#define clz(n) (__builtin_clzll((n)))
#define ctz(n) (__builtin_ctzll((n)))
#define lg(n) (63 - __builtin_clzll((n)))
#define BIT(n, i) (((n) >> (i)) & 1ll)
#define MASK(i) (1ll << (i))
#define FLIP(n, i) ((n) ^ (1ll << (i)))
#define ON(n, i) ((n) | MASK(i))
#define OFF(n, i) ((n) & ~MASK(i))
#define Int __int128
#define fi first
#define se second
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
typedef pair<long long, int> pli;
typedef pair<int, long long> pil;
typedef vector<pair<int, int>> vii;
typedef vector<pair<long long, long long>> vll;
typedef vector<pair<long long, int>> vli;
typedef vector<pair<int, long long>> vil;
template <class T1, class T2>
bool maximize(T1 &x, T2 y) {
if (x < y) {
x = y;
return true;
}
return false;
}
template <class T1, class T2>
bool minimize(T1 &x, T2 y) {
if (x > y) {
x = y;
return true;
}
return false;
}
template <class T>
void remove_duplicate(vector<T> &ve) {
sort (ve.begin(), ve.end());
ve.resize(unique(ve.begin(), ve.end()) - ve.begin());
}
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
template <class T> T random(T l, T r) {
return uniform_int_distribution<T>(l, r)(rng);
}
template <class T> T random(T r) {
return rng() % r;
}
const int N = 2e5 + 5, K = 1e6 + 5;
const int MOD = 1e9 + 7;
const int inf = 1e9;
const ll INF = 1e18;
int n, k, ans = inf;
int sz[N], f[K];
vector<int> all_lengths;
vii adj[N];
bitset<N> deleted;
void count_child(int u, int fa) {
sz[u] = 1;
for (auto it : adj[u]) {
int v = it.fi;
if (v != fa && !deleted[v]) {
count_child(v, u);
sz[u] += sz[v];
}
}
}
int get_centroid(const int n, int u, int fa) {
for (auto it : adj[u]) {
int v = it.fi;
if (v != fa && !deleted[v] && 2 * sz[v] > n) return get_centroid(n, v, u);
}
return u;
}
void dfs(int u, int fa, int depth, int length, bool update) {
if (length > k) return;
if (update) {
minimize(f[length], depth);
all_lengths.emplace_back(length);
}
else minimize(ans, depth + f[k - length]);
for (auto it : adj[u]) {
int v = it.fi, w = it.se;
if (v != fa && !deleted[v]) dfs(v, u, depth + 1, length + w, update);
}
}
void centroid_decomp(int u) {
count_child(u, -1); int centroid = get_centroid(sz[u], u, -1);
deleted[centroid] = true;
all_lengths.clear();
for (auto it : adj[u]) {
int v = it.fi, w = it.se;
if (!deleted[v]) {
dfs(v, u, 1, w, false);
dfs(v, u, 1, w, true);
}
}
for (auto length : all_lengths) f[length] = inf;
for (auto it : adj[u]) if (!deleted[it.fi]) {
centroid_decomp(it.fi);
}
}
int best_path(int _n, int _k, int H[][2], int L[]) {
n = _n, k = _k;
for (int i = 0; i < n - 1; ++i) {
int u = H[i][0], v = H[i][1], w = L[i];
adj[u].emplace_back(v, w),
adj[v].emplace_back(u, w);
}
ans = inf; centroid_decomp(1);
return ans;
}
#ifdef hwe
signed main() {
ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
cerr << '\n'; return 0;
}
#endif
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
12636 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
12636 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
12636 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
12636 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
