oj.uz

답안 #575880

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
575880 2022-06-11T13:18:25 Z eecs Papričice (COCI20_papricice) C++17
0 / 110
 8 ms 14424 KB 
#include <bits/stdc++.h>
using namespace std;

const int maxn = 200010;
int n, ans = INT_MAX, sz[maxn], fa[maxn];
vector<int> G[maxn];
set<int> S[maxn];

int main() {
    ios::sync_with_stdio(0), cin.tie(0);
    cin >> n;
    for (int i = 1, u, v; i < n; i++) {
        cin >> u >> v;
        G[u].push_back(v), G[v].push_back(u);
    }
    auto chk = [&](int a, int b, int c) {
        if (a && b && c) ans = min(ans, max({a, b, c}) - min({a, b, c}));
    };
    auto dfs = [&](auto self, int u) -> void {
        sz[u] = 1;
        for (int v : G[u]) if (v ^ fa[u]) {
            fa[v] = u, self(self, v), sz[u] += sz[v];
            if (S[u].size() < S[v].size()) swap(S[u], S[v]);
            for (int x : S[v]) S[u].insert(x);
        }
        S[u].insert(sz[u]);
        auto it = S[u].lower_bound(sz[u] / 2);
        chk(*it, sz[u] - *it, n - sz[u]);
        if (it != S[u].begin()) chk(*prev(it), sz[u] - *prev(it), n - sz[u]);
    };
    dfs(dfs, 1);
    cout << ans << "\n";
    return 0;
}

Subtask #1
0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 8 ms 14420 KB Output is correct
2 Correct 8 ms 14424 KB Output is correct
3 Incorrect 8 ms 14324 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #2
0 / 35.0

# 결과 실행 시간 메모리 Grader output
1 Correct 8 ms 14420 KB Output is correct
2 Correct 8 ms 14424 KB Output is correct
3 Incorrect 8 ms 14324 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #3
0 / 60.0

# 결과 실행 시간 메모리 Grader output
1 Correct 8 ms 14420 KB Output is correct
2 Correct 8 ms 14424 KB Output is correct
3 Incorrect 8 ms 14324 KB Output isn't correct
4 Halted 0 ms 0 KB -