Submission #1362262

#	Time	Username	Problem	Language	Result	Execution time	Memory
1362262		po_rag526	Duathlon (APIO18_duathlon)	C++20	0 / 100	1 ms	344 KiB

count_triplets

#include<bits/stdc++.h>

using namespace std;

#define ll long long
const int maxn=55;
ll n,m,s,f,ans=0;
bitset<maxn>vis,anss;
vector<ll>v[maxn];
void dfs(ll x){
    vis[x]=1;
    if(x==f){
        anss|=vis;
        vis[x]=0;
        return;
    }
    for(auto i:v[x]) if(!vis[i]) dfs(i);
    vis[x]=0;
}
void solve(){
    cin>>n>>m;
    for(int i=0;i<m;i++){
        ll a,b;
        cin>>a>>b;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    for(int i=1;i<=n;i++){
        for(int j=1;j<=n;j++){
            if(i==j) continue;
            s=i,f=j;
            dfs(i);
            ans+=anss.count()-2;
            anss.reset();
        }
    }
    cout<<ans;
}

int main(){
    ios_base::sync_with_stdio(0);cin.tie(0);
    int _=1;
    // cin>>_;
    while(_--) solve();
}

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