Submission #1228654

#	Time	Username	Problem	Language	Result	Execution time	Memory
1228654		irina	Three Friends (BOI14_friends)	C++20	0 / 100	23 ms	4152 KiB

friends

#include<bits/stdc++.h>
using namespace std;
string u;
long long vis[27],ans,w;
int main(){
    long long n;
    cin>>n;
    cin>>u;
    for(int i=0;i<n;i++){
        int y=u[i]-'A'+1;
        vis[y]++;
    }
    if(n%2==0){
        cout<<"NOT POSSIBLE";
        return 0;
    }
    for(int i=1;i<27;i++){
        if(vis[i]>2&&vis[i]%2==1){
            cout<<"NOT UNIQUE";
            return 0;
        }
        if(vis[i]==1)ans++;
    }
    if(ans>1){
        cout<<"NOT POSSIBLE";
        return 0;
    }
    if(n%2==0){
        cout<<"NOT POSSIBLE";
        return 0;
    }
    for(int i=0;i<n;i++){
        if(w>=n/2)return 0;
        if(vis[u[i]-'A'+1]%2==0){
            cout<<u[i];
            w++;
        }
    }
    return 0;
}

• Subtask 1: 0 / 35
• Subtask 2: 0 / 65