#pragma GCC optimize("Ofast")
#pragma GCC optimization("unroll-loops")
#pragma GCC target("avx,avx2,fma")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/trie_policy.hpp>
#include <ext/rope>
using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define fi first
#define se second
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define gcd __gcd
#define fastio ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define rep(i, n) for (int i=0; i<(n); i++)
#define rep1(i, n) for (int i=1; i<=(n); i++)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define endl "\n"
typedef long long ll;
typedef unsigned long long ull;
typedef unsigned uint;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<vector<int>> vvi;
typedef vector<ll> vll;
typedef vector<vector<ll>> vvll;
typedef vector<bool> vb;
typedef vector<vector<bool>> vvb;
template<typename T, typename cmp = less<T>>
using ordered_set=tree<T, null_type, cmp, rb_tree_tag, tree_order_statistics_node_update>;
typedef trie<string, null_type, trie_string_access_traits<>, pat_trie_tag, trie_prefix_search_node_update> pref_trie;
constexpr int N = 1e6 + 5;
bool path[N];
vi adj[N];
int dp[N];
void dfs(int u, int p = -1) {
int sum = 0, mx = -1, cnt = 0;
for(int v: adj[u]) if(v != p) {
dfs(v, u);
if(!path[v]) {
sum += dp[v];
mx = max(mx, dp[v]);
cnt++;
}
else path[u] = 1;
}
if(!cnt) dp[u] = 0;
else dp[u] = sum - mx + cnt;
}
int32_t main() {
fastio;
int n, t, m; cin >> n >> t >> m; --t, --m;
path[m] = 1;
rep(_, n - 1) {
int u, v; cin >> u >> v; --u, --v;
adj[u].eb(v);
adj[v].eb(u);
}
dfs(t);
int ans = 0;
rep(i, n) if(path[i] && i != t) ans += dp[i];
cout << ans << endl;
}
Compilation message
mousetrap.cpp:2: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
2 | #pragma GCC optimization("unroll-loops")
|
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
18 ms |
23812 KB |
Output is correct |
2 |
Correct |
14 ms |
23756 KB |
Output is correct |
3 |
Correct |
14 ms |
23756 KB |
Output is correct |
4 |
Correct |
14 ms |
23784 KB |
Output is correct |
5 |
Incorrect |
15 ms |
23756 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
260 ms |
72380 KB |
Output is correct |
2 |
Correct |
236 ms |
67392 KB |
Output is correct |
3 |
Incorrect |
672 ms |
73320 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
18 ms |
23812 KB |
Output is correct |
2 |
Correct |
14 ms |
23756 KB |
Output is correct |
3 |
Correct |
14 ms |
23756 KB |
Output is correct |
4 |
Correct |
14 ms |
23784 KB |
Output is correct |
5 |
Incorrect |
15 ms |
23756 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
18 ms |
23812 KB |
Output is correct |
2 |
Correct |
14 ms |
23756 KB |
Output is correct |
3 |
Correct |
14 ms |
23756 KB |
Output is correct |
4 |
Correct |
14 ms |
23784 KB |
Output is correct |
5 |
Incorrect |
15 ms |
23756 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |