Submission #552391

#	Time	Username	Problem	Language	Result	Execution time	Memory
552391		zaneyu	Duathlon (APIO18_duathlon)	C++14	10 / 100	1084 ms	12204 KiB

count_triplets

/*input
4 4
1 2
2 3
3 4
4 2
*/
#include<bits/stdc++.h>
using namespace std;
#define REP(i,n) for(int i=0;i<n;i++)
const int maxn=1e5+5;
#define pb push_back
#define ll long long
int dep[maxn];
bool vis[maxn];
vector<int> v[maxn];
ll ans=0;
void dfs(int u){
    vis[u]=1;
    if(dep[u]>1) ans+=dep[u]-1;
    for(int x:v[u]){
        if(!vis[x]){
            dep[x]=dep[u]+1;
            dfs(x);
        }
    }
}
int main(){
    ios::sync_with_stdio(false),cin.tie(0);
    int n,m;
    cin>>n>>m;
    REP(i,m){
        int a,b;
        cin>>a>>b;
        --a,--b;
        v[a].pb(b),v[b].pb(a);
    }
    REP(i,n){
        REP(j,n) vis[j]=0;
        dep[i]=0;
        dfs(i);
    }
    cout<<ans<<'\n';
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 11
• Subtask 3: 0 / 8
• Subtask 4: 10 / 10
• Subtask 5: 0 / 13
• Subtask 6: 0 / 15
• Subtask 7: 0 / 20
• Subtask 8: 0 / 8
• Subtask 9: 0 / 10