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QOJ
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 |
---|---|---|---|---|---|---|---|---|---|
#153262 | #6865. foreverlasting and fried-chicken | neko_nyaa | WA | 484ms | 3648kb | C++23 | 1.0kb | 2023-08-29 19:39:02 | 2023-08-29 19:39:03 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
#define int long long
const int M = 1000000007;
int modpow(int n, int k) {
int ans = 1;
while (k) {
if (k % 2) ans = (ans*n) % M;
n = (n*n) % M; k /= 2;
}
return ans;
}
int c4(int n) {
int p = n*(n-1)*(n-2)*(n-3);
int q = 1*2*3*4;
return p*modpow(q, M-2) % M;
}
int c2(int n) {
int p = n*(n-1);
int q = 1*2;
return p*modpow(q, M-2) % M;
}
typedef bitset<1000> bs;
void solve() {
int n, m; cin >> n >> m;
vector<bs> adj(n);
while (m--) {
int x, y; cin >> x >> y; x--, y--;
adj[x][y] = adj[y][x] = 1;
}
int ans = 0;
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
if (i == j) continue;
int up = adj[i].count();
int down = (adj[i] & adj[j]).count();
if (up < 6 || down < 4) continue;
int tmp = c4(down);
tmp = (tmp*c2(up-4)) % M;
ans = (ans+tmp) % M;
}
}
cout << ans << '\n';
}
signed main() {
ios::sync_with_stdio(0); cin.tie(0);
int t; cin >> t;
while (t--) {
solve();
}
return 0;
}
詳細信息
Test #1:
score: 0
Wrong Answer
time: 484ms
memory: 3648kb
input:
9 8 10 1 2 1 3 1 4 1 5 1 6 1 7 8 4 8 5 8 6 8 7 10 12 1 2 1 3 1 4 1 5 1 6 1 7 8 4 8 5 8 6 8 7 8 9 8 10 11 13 1 2 1 3 1 4 1 5 1 6 1 7 8 4 8 5 8 6 8 7 8 9 8 10 1 11 11 14 1 2 1 3 1 4 1 5 1 6 1 7 8 4 8 5 8 6 8 7 8 9 8 10 1 11 1 8 10 45 5 10 2 9 5 8 3 10 2 10 4 9 4 3 4 2 5 6 7 1 10 6 10 7 6 1 8 3 5 1 7 5...
output:
1 2 4 9 63000 0 624414727 755929618 4088223
result:
wrong answer 4th lines differ - expected: '4', found: '9'