oj.uz

답안 #19875

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
19875 2016-02-25T06:30:05 Z tonyjjw 트리 (kriii4_X) C++14
100 / 100
 102 ms 6244 KB 
//*
#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<algorithm>
#include<vector>
#define all(A) (A).begin(), (A).end()

using namespace std;

typedef long long ll;
typedef pair<int,int> pii;

const int MM = 200000;
const ll mod = 1000000007;

ll N;
int M;
int A[MM],B[MM];
int par[MM];
int cnt[MM];
int nN;

int getpar(int n){
	if(par[n]==n)return n;
	return par[n]=getpar(par[n]);
}

bool merge(int a,int b){
	if(getpar(a)==getpar(b))return true;
	par[getpar(a)]=getpar(b);
	return false;
}

ll mpow(ll a,ll p){
	ll r=1;
	while(p>0){
		if(p&1)r=r*a%mod;
		a=a*a%mod;
		p>>=1;
	}
	return r;
}

int main(){
	scanf("%lld%d",&N,&M);
	vector<int> nodes;
	for(int i=0;i<M;i++){
		scanf("%d%d",&A[i],&B[i]);
		nodes.push_back(A[i]),nodes.push_back(B[i]);
	}
	sort(all(nodes));
	nodes.resize(unique(all(nodes))-nodes.begin());
	for(int i=0;i<M;i++){
		A[i]=lower_bound(all(nodes),A[i])-nodes.begin();
		B[i]=lower_bound(all(nodes),B[i])-nodes.begin();
	}
	nN=nodes.size();
	for(int i=0;i<nN;i++)par[i]=i;
	for(int i=0;i<M;i++){
		if(merge(A[i],B[i]))return !printf("0\n");
	}
	if(M==N-1){
		return !printf("1\n");
	}
	for(int i=0;i<nN;i++){
		cnt[getpar(i)]++;
	}
	ll ans=mpow(N,N-M-2);
	for(int i=0;i<nN;i++)if(par[i]==i){
		ans*=cnt[i];
		ans%=mod;
	}
	printf("%lld\n",ans);
	return 0;
}
//*/

Subtask #1
9.0 / 9.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 4704 KB Output is correct
2 Correct 0 ms 4704 KB Output is correct
3 Correct 0 ms 4704 KB Output is correct
4 Correct 0 ms 4704 KB Output is correct
5 Correct 0 ms 4704 KB Output is correct
6 Correct 0 ms 4704 KB Output is correct
7 Correct 0 ms 4704 KB Output is correct
8 Correct 0 ms 4704 KB Output is correct
9 Correct 0 ms 4704 KB Output is correct
10 Correct 0 ms 4704 KB Output is correct
11 Correct 0 ms 4704 KB Output is correct
12 Correct 0 ms 4704 KB Output is correct
13 Correct 0 ms 4704 KB Output is correct
14 Correct 0 ms 4704 KB Output is correct
15 Correct 0 ms 4704 KB Output is correct
16 Correct 0 ms 4704 KB Output is correct
17 Correct 0 ms 4704 KB Output is correct
18 Correct 0 ms 4704 KB Output is correct
19 Correct 0 ms 4704 KB Output is correct
20 Correct 0 ms 4704 KB Output is correct
21 Correct 0 ms 4704 KB Output is correct
22 Correct 0 ms 4704 KB Output is correct
23 Correct 0 ms 4704 KB Output is correct
24 Correct 0 ms 4704 KB Output is correct
25 Correct 0 ms 4704 KB Output is correct
26 Correct 0 ms 4704 KB Output is correct
27 Correct 0 ms 4704 KB Output is correct
28 Correct 0 ms 4704 KB Output is correct
29 Correct 0 ms 4704 KB Output is correct
30 Correct 0 ms 4704 KB Output is correct

Subtask #2
91.0 / 91.0

# 결과 실행 시간 메모리 Grader output
1 Correct 10 ms 4836 KB Output is correct
2 Correct 21 ms 5092 KB Output is correct
3 Correct 18 ms 5092 KB Output is correct
4 Correct 9 ms 4836 KB Output is correct
5 Correct 16 ms 5092 KB Output is correct
6 Correct 95 ms 6244 KB Output is correct
7 Correct 86 ms 6244 KB Output is correct
8 Correct 66 ms 6244 KB Output is correct
9 Correct 96 ms 6244 KB Output is correct
10 Correct 77 ms 6244 KB Output is correct
11 Correct 94 ms 6244 KB Output is correct
12 Correct 86 ms 6244 KB Output is correct
13 Correct 89 ms 6244 KB Output is correct
14 Correct 88 ms 6244 KB Output is correct
15 Correct 84 ms 6244 KB Output is correct
16 Correct 97 ms 6244 KB Output is correct
17 Correct 84 ms 6244 KB Output is correct
18 Correct 0 ms 4704 KB Output is correct
19 Correct 94 ms 6244 KB Output is correct
20 Correct 98 ms 6244 KB Output is correct
21 Correct 95 ms 6244 KB Output is correct
22 Correct 88 ms 6244 KB Output is correct
23 Correct 83 ms 6244 KB Output is correct
24 Correct 82 ms 6244 KB Output is correct
25 Correct 64 ms 6244 KB Output is correct
26 Correct 59 ms 6244 KB Output is correct
27 Correct 102 ms 6244 KB Output is correct
28 Correct 101 ms 6244 KB Output is correct
29 Correct 95 ms 6244 KB Output is correct
30 Correct 95 ms 6244 KB Output is correct