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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#213611#2715. 8.4t4yanruo_BGSSR_ypa2044ms1380kbC++11748b2024-11-12 21:42:232024-11-12 23:56:34

answer

#include<bits/stdc++.h>
#define int long long
using namespace std;
const int mod=1e9+7;
int n;
vector<int>e[5001];
bool vis[5001];
void cz(vector<int>&c,int x,int fa){
    c.push_back(x);
    for(auto p:e[x]){
        if(vis[p]||p==fa)continue;
        cz(c,p,x);
    }
}
int js(int x){
    int ret=0;
    vector<int>c;
    cz(c,x,-1);
    for(auto w:c){
        int t=1;
        vis[w]=1;
        for(auto p:e[w]){
            if(vis[p])continue;
            (t*=js(p))%=mod;
        }
        vis[w]=0,(ret+=t)%=mod;
    }
    return ret;
}
signed main(){
	ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
	cin>>n;
	for(int i=1,u,v;i<n;i++)cin>>u>>v,e[u].push_back(v),e[v].push_back(u);
	return cout<<js(1),0;
}

Details

小提示:点击横条可展开更详细的信息

Test #1:

score: 10
Accepted
time: 34ms
memory: 1380kb

input:

10
1 2
1 3
3 4
3 5
3 6
3 7
1 8
5 9
5 10

output:

227506

result:

ok found '227506.00000', expected '227506.00000', error '0.00000'

Test #2:

score: 10
Accepted
time: 10ms
memory: 1380kb

input:

10
1 2
1 3
3 4
4 5
5 6
4 7
5 8
8 9
8 10

output:

70140

result:

ok found '70140.00000', expected '70140.00000', error '0.00000'

Test #3:

score: 0
Time Limit Exceeded

input:

100
1 2
1 3
1 4
3 5
5 6
4 7
7 8
8 9
8 10
3 11
7 12
1 13
5 14
8 15
10 16
7 17
1 18
6 19
10 20
15 21
7...

output:


result:


Test #4:

score: 0
Time Limit Exceeded

input:

100
1 2
2 3
3 4
4 5
4 6
6 7
5 8
8 9
8 10
1 11
6 12
4 13
9 14
13 15
7 16
3 17
15 18
17 19
9 20
8 21
4...

output:


result:


Test #5:

score: 0
Time Limit Exceeded

input:

100
1 2
2 3
3 4
2 5
2 6
5 7
2 8
4 9
7 10
5 11
11 12
6 13
8 14
13 15
5 16
11 17
16 18
11 19
7 20
19 2...

output:


result:


Test #6:

score: 0
Time Limit Exceeded

input:

500
1 2
1 3
3 4
3 5
5 6
1 7
3 8
8 9
4 10
6 11
7 12
2 13
11 14
8 15
7 16
9 17
2 18
3 19
15 20
2 21
20...

output:


result:


Test #7:

score: 0
Time Limit Exceeded

input:

500
1 2
1 3
1 4
2 5
5 6
5 7
4 8
8 9
1 10
4 11
8 12
6 13
13 14
13 15
12 16
1 17
10 18
13 19
1 20
1 21...

output:


result:


Test #8:

score: 0
Time Limit Exceeded

input:

5000
1 2
1 3
1 4
3 5
3 6
5 7
4 8
4 9
1 10
5 11
6 12
10 13
12 14
14 15
12 16
8 17
14 18
9 19
8 20
20 ...

output:


result:


Test #9:

score: 0
Time Limit Exceeded

input:

5000
1 2
1 3
1 4
2 5
1 6
5 7
2 8
5 9
4 10
9 11
10 12
8 13
7 14
13 15
12 16
5 17
9 18
8 19
3 20
4 21
...

output:


result:


Test #10:

score: 0
Time Limit Exceeded

input:

5000
1 2
1 3
1 4
4 5
4 6
3 7
2 8
8 9
6 10
9 11
3 12
3 13
7 14
13 15
4 16
10 17
9 18
10 19
5 20
17 21...

output:


result: