oj.uz

답안 #43271

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
43271 2018-03-12T12:59:20 Z ffresh 우호 조약 체결 (JOI14_friends) C++14
100 / 100
 154 ms 12416 KB 
#include <bits/stdc++.h>

using namespace std;

const int N = 1e5+15;

long long par[N],sz[N],esz[N];

vector<int> adj[N];

int f(int a){
	if(a==par[a])return a;
	return par[a]= f(par[a]);
}
void merge(int a,int b){
	a= f(a),b= f(b);
	if(a!=b){
		par[b]= a;
		sz[a]+=sz[b];
		esz[a]+=esz[b];
	}
	++esz[a];
}
bool vis[N];

void dfs(int root){
	vis[root]= 1;
	for(int i=0;i<adj[root].size();++i){
		int u = adj[root][i];
		if(!vis[u]){
			dfs(u);
		}
		merge(u,root);
	}
}


int main(){
	//freopen("input.txt","r",stdin);
	int n,m,a,b;
	scanf("%d%d",&n,&m);
	assert(n<=1e5);
	for(int i=0;i<m;++i){
		scanf("%d%d",&a,&b);
		adj[a].push_back(b);
	}
	for(int i=1;i<=n;++i)
		par[i] =i,sz[i]= 1;
	for(int i=1;i<=n;++i){
		if((int)adj[i].size()>=2){
			int cur = adj[i][0],v;
			for(int j=0;j<adj[i].size();++j){
				int u = adj[i][j];
				if(!vis[u])
					dfs(u);
				if(f(u)!=f(cur)){
					v = f(cur),u = f(u);
					par[u] = v;
					esz[v]+=esz[u];
					sz[v] += sz[u];
				}
			}
		}
	}
	
	long long ret=0;
	for(int i=1;i<=n;++i){
		if(f(i)==i){
			ret += (long long)(sz[i]*(sz[i]-1));
			ret -= esz[i];
		}
	}
	ret+=m;
	cout<<ret<<endl;
}

Compilation message

friends.cpp: In function 'void dfs(int)':
friends.cpp:28:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<adj[root].size();++i){
               ^
friends.cpp: In function 'int main()':
friends.cpp:52:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int j=0;j<adj[i].size();++j){
                 ^
friends.cpp:41:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n,&m);
                     ^
friends.cpp:44:22: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d",&a,&b);
                      ^

Subtask #1
5.0 / 5.0

# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 2680 KB Output is correct
2 Correct 3 ms 2784 KB Output is correct
3 Correct 4 ms 2784 KB Output is correct
4 Correct 3 ms 2808 KB Output is correct
5 Correct 3 ms 2844 KB Output is correct
6 Correct 3 ms 2844 KB Output is correct
7 Correct 4 ms 2912 KB Output is correct
8 Correct 4 ms 2912 KB Output is correct
9 Correct 4 ms 2924 KB Output is correct
10 Correct 3 ms 2924 KB Output is correct
11 Correct 3 ms 2924 KB Output is correct
12 Correct 4 ms 2924 KB Output is correct
13 Correct 4 ms 2924 KB Output is correct
14 Correct 3 ms 2924 KB Output is correct
15 Correct 3 ms 2924 KB Output is correct
16 Correct 3 ms 2924 KB Output is correct
17 Correct 4 ms 2992 KB Output is correct
18 Correct 3 ms 2992 KB Output is correct

Subtask #2
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 3184 KB Output is correct
2 Correct 4 ms 3184 KB Output is correct
3 Correct 11 ms 3436 KB Output is correct
4 Correct 48 ms 4312 KB Output is correct
5 Correct 41 ms 4312 KB Output is correct
6 Correct 65 ms 4656 KB Output is correct
7 Correct 4 ms 4656 KB Output is correct
8 Correct 7 ms 4656 KB Output is correct
9 Correct 12 ms 4656 KB Output is correct
10 Correct 22 ms 4656 KB Output is correct
11 Correct 63 ms 4720 KB Output is correct
12 Correct 15 ms 4720 KB Output is correct
13 Correct 6 ms 4720 KB Output is correct
14 Correct 5 ms 4720 KB Output is correct
15 Correct 7 ms 4720 KB Output is correct
16 Correct 15 ms 4720 KB Output is correct
17 Correct 59 ms 4720 KB Output is correct
18 Correct 5 ms 4720 KB Output is correct
19 Correct 5 ms 4720 KB Output is correct
20 Correct 67 ms 4824 KB Output is correct
21 Correct 5 ms 4824 KB Output is correct
22 Correct 5 ms 4824 KB Output is correct
23 Correct 8 ms 4824 KB Output is correct
24 Correct 5 ms 4824 KB Output is correct
25 Correct 5 ms 4824 KB Output is correct
26 Correct 5 ms 4824 KB Output is correct
27 Correct 5 ms 4824 KB Output is correct
28 Correct 5 ms 4824 KB Output is correct

Subtask #3
65.0 / 65.0

# 결과 실행 시간 메모리 Grader output
1 Correct 58 ms 4824 KB Output is correct
2 Correct 125 ms 9516 KB Output is correct
3 Correct 135 ms 9516 KB Output is correct
4 Correct 62 ms 9516 KB Output is correct
5 Correct 31 ms 9516 KB Output is correct
6 Correct 107 ms 9516 KB Output is correct
7 Correct 89 ms 9516 KB Output is correct
8 Correct 92 ms 9516 KB Output is correct
9 Correct 58 ms 9516 KB Output is correct
10 Correct 80 ms 9516 KB Output is correct
11 Correct 134 ms 9516 KB Output is correct
12 Correct 122 ms 10348 KB Output is correct
13 Correct 44 ms 10348 KB Output is correct
14 Correct 72 ms 10348 KB Output is correct
15 Correct 28 ms 10348 KB Output is correct
16 Correct 6 ms 10348 KB Output is correct
17 Correct 5 ms 10348 KB Output is correct
18 Correct 124 ms 10348 KB Output is correct
19 Correct 121 ms 10348 KB Output is correct
20 Correct 60 ms 10348 KB Output is correct
21 Correct 30 ms 10348 KB Output is correct
22 Correct 5 ms 10348 KB Output is correct
23 Correct 34 ms 10348 KB Output is correct
24 Correct 67 ms 10348 KB Output is correct
25 Correct 46 ms 10348 KB Output is correct
26 Correct 61 ms 12416 KB Output is correct
27 Correct 120 ms 12416 KB Output is correct
28 Correct 51 ms 12416 KB Output is correct
29 Correct 54 ms 12416 KB Output is correct
30 Correct 154 ms 12416 KB Output is correct
31 Correct 55 ms 12416 KB Output is correct
32 Correct 46 ms 12416 KB Output is correct
33 Correct 46 ms 12416 KB Output is correct
34 Correct 64 ms 12416 KB Output is correct
35 Correct 55 ms 12416 KB Output is correct
36 Correct 53 ms 12416 KB Output is correct
37 Correct 50 ms 12416 KB Output is correct