#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ar array
const int M=1e9+7;
int n, m, k;
vector<ar<int, 2>> adj[60];
vector<int> cur, e[15];
ll a2[60], kp[60];
bool vis[60];
void dfs(int u, int p, int t, int i) {
if (u==t) {
e[i]=cur;
return;
}
for (ar<int, 2> v : adj[u]) {
if (v[0]==p)
continue;
cur.push_back(v[1]);
dfs(v[0], u, t, i);
cur.pop_back();
}
}
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
cin >> n >> m >> k;
for (int i=1; i<n; ++i) {
int u, v;
cin >> u >> v, --u, --v;
adj[u].push_back({v, i});
adj[v].push_back({u, i});
}
for (int i=0; i<m; ++i) {
int u, v;
cin >> u >> v, --u, --v;
dfs(u, -1, v, i);
}
kp[0]=1;
for (int i=1; i<n; ++i)
kp[i]=kp[i-1]*k%M;
ll ans=0;
for (int i=0; i<(1<<m); ++i) {
memset(a2, 0, sizeof(a2));
for (int j=0; j<m; ++j)
if (i&1<<j)
for (int x=1; x<e[j].size(); ++x) {
a2[e[j][0]]|=1ll<<e[j][x];
a2[e[j][x]]|=1ll<<e[j][0];
}
memset(vis, 0, sizeof(vis));
int cmp=0;
for (int i=1; i<n; ++i) {
if (vis[i])
continue;
++cmp;
ll all=0, q=1ll<<i;
while(all!=q) {
int bit=__builtin_ctzll(all^q);
vis[bit]=1;
all|=1ll<<bit;
q|=a2[bit];
}
}
ans=(ans+(__builtin_popcount(i)%2==0?1:-1)*kp[cmp]+M)%M;
}
cout << ans;
return 0;
}
Compilation message
Main.cpp: In function 'int main()':
Main.cpp:51:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
51 | for (int x=1; x<e[j].size(); ++x) {
| ~^~~~~~~~~~~~
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
0 ms |
204 KB |
Output is correct |
| 2 |
Correct |
0 ms |
312 KB |
Output is correct |
| 3 |
Correct |
1 ms |
204 KB |
Output is correct |
| 4 |
Correct |
0 ms |
312 KB |
Output is correct |
| 5 |
Correct |
1 ms |
204 KB |
Output is correct |
| 6 |
Correct |
1 ms |
312 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1 ms |
204 KB |
Output is correct |
| 2 |
Correct |
1 ms |
204 KB |
Output is correct |
| 3 |
Correct |
1 ms |
204 KB |
Output is correct |
| 4 |
Correct |
0 ms |
204 KB |
Output is correct |
| 5 |
Correct |
1 ms |
204 KB |
Output is correct |
| 6 |
Correct |
1 ms |
204 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1 ms |
320 KB |
Output is correct |
| 2 |
Correct |
0 ms |
204 KB |
Output is correct |
| 3 |
Correct |
0 ms |
316 KB |
Output is correct |
| 4 |
Correct |
1 ms |
204 KB |
Output is correct |
| 5 |
Correct |
2 ms |
204 KB |
Output is correct |
| 6 |
Correct |
1 ms |
320 KB |
Output is correct |
| 7 |
Correct |
1 ms |
204 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
0 ms |
312 KB |
Output is correct |
| 2 |
Correct |
0 ms |
204 KB |
Output is correct |
| 3 |
Correct |
1 ms |
204 KB |
Output is correct |
| 4 |
Correct |
0 ms |
204 KB |
Output is correct |
| 5 |
Correct |
2 ms |
204 KB |
Output is correct |
| 6 |
Correct |
2 ms |
204 KB |
Output is correct |
| 7 |
Correct |
1 ms |
204 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
0 ms |
204 KB |
Output is correct |
| 2 |
Correct |
0 ms |
312 KB |
Output is correct |
| 3 |
Correct |
1 ms |
204 KB |
Output is correct |
| 4 |
Correct |
0 ms |
312 KB |
Output is correct |
| 5 |
Correct |
1 ms |
204 KB |
Output is correct |
| 6 |
Correct |
1 ms |
312 KB |
Output is correct |
| 7 |
Correct |
1 ms |
204 KB |
Output is correct |
| 8 |
Correct |
1 ms |
204 KB |
Output is correct |
| 9 |
Correct |
1 ms |
204 KB |
Output is correct |
| 10 |
Correct |
0 ms |
204 KB |
Output is correct |
| 11 |
Correct |
1 ms |
204 KB |
Output is correct |
| 12 |
Correct |
1 ms |
204 KB |
Output is correct |
| 13 |
Correct |
1 ms |
320 KB |
Output is correct |
| 14 |
Correct |
0 ms |
204 KB |
Output is correct |
| 15 |
Correct |
0 ms |
316 KB |
Output is correct |
| 16 |
Correct |
1 ms |
204 KB |
Output is correct |
| 17 |
Correct |
2 ms |
204 KB |
Output is correct |
| 18 |
Correct |
1 ms |
320 KB |
Output is correct |
| 19 |
Correct |
1 ms |
204 KB |
Output is correct |
| 20 |
Correct |
0 ms |
312 KB |
Output is correct |
| 21 |
Correct |
0 ms |
204 KB |
Output is correct |
| 22 |
Correct |
1 ms |
204 KB |
Output is correct |
| 23 |
Correct |
0 ms |
204 KB |
Output is correct |
| 24 |
Correct |
2 ms |
204 KB |
Output is correct |
| 25 |
Correct |
2 ms |
204 KB |
Output is correct |
| 26 |
Correct |
1 ms |
204 KB |
Output is correct |
| 27 |
Correct |
6 ms |
312 KB |
Output is correct |
| 28 |
Correct |
0 ms |
204 KB |
Output is correct |
| 29 |
Correct |
1 ms |
204 KB |
Output is correct |
| 30 |
Correct |
6 ms |
316 KB |
Output is correct |
| 31 |
Correct |
2 ms |
204 KB |
Output is correct |
| 32 |
Correct |
1 ms |
204 KB |
Output is correct |
| 33 |
Correct |
1 ms |
204 KB |
Output is correct |
| 34 |
Correct |
1 ms |
204 KB |
Output is correct |
| 35 |
Correct |
4 ms |
204 KB |
Output is correct |
| 36 |
Correct |
12 ms |
204 KB |
Output is correct |
| 37 |
Correct |
6 ms |
204 KB |
Output is correct |
