Submission #861935

#	Time	Username	Problem	Language	Result	Execution time	Memory
861935		HossamHero7	Logičari (COCI21_logicari)	C++14	20 / 110	30 ms	7056 KiB

Main

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define endl '\n'
void solve(){
    int n;
    cin>>n;
    vector<vector<int>> adj(n);
    for(int i=1;i<=n;i++){
        int a,b;
        cin>>a>>b;
        a --, b --;
        adj[a].push_back(b);
        adj[b].push_back(a);
    }
    if(n <= 20){
        int ans = 1e9;
        for(int mask=0;mask<(1<<n);mask++){
            bitset<21> on;
            for(int i=0;i<n;i++) on[i] = (mask>>i)&1;
            for(int i=0;i<n;i++){
                int cnt = 0;
                for(auto ch : adj[i]) cnt += on[ch];
                if(cnt != 1) goto gt;
            }
            ans = min(ans,(int)on.count());
            gt: continue;
        }
        cout<<(ans == 1e9 ? -1 : ans)<<endl;
    }
    else {
        if(n%4 == 0) cout<<n/2<<endl;
        else cout<<-1<<endl;
    }
}
int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);      cout.tie(0);
    int t=1;
    //cin>>t;
    while(t--){
        solve();
    }
    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 40
• Subtask 4: 0 / 50