Submission #930729

#	Time	Username	Problem	Language	Result	Execution time	Memory
930729		emptypringlescan	Three Friends (BOI14_friends)	C++17	100 / 100	12 ms	8196 KiB

friends

#include <bits/stdc++.h>
using namespace std;
int32_t main(){
    ios::sync_with_stdio(0);cin.tie(0);
    int n;
    cin >> n;
    if(n%2==0||n<3){
		cout << "NOT POSSIBLE";
		return 0;
	}
    string s;
    cin >> s;
    set<string> ans;
    string a="",b="";
    int mid=n/2;
    for(int i=mid+1; i<n; i++) a+=s[i];
    int p1,p2;
    for(p1=0; p1<mid; p1++){
		if(s[p1]!=a[p1]) break;
	}
	for(p2=mid; p2>0; p2--){
		if(s[p2]!=a[p2-1]) break;
	}
	if(p1>=p2) ans.insert(a);
	for(int i=0; i<mid; i++) b+=s[i];
    for(p1=mid; p1<n-1; p1++){
		if(s[p1]!=b[p1-mid]) break;
	}
	for(p2=n-1; p2>mid; p2--){
		if(s[p2]!=b[p2-1-mid]) break;
	}
	if(p1>=p2) ans.insert(b);
	if(ans.size()>1) cout << "NOT UNIQUE";
	else if(ans.size()==1) cout << *ans.begin();
	else cout << "NOT POSSIBLE";
}

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