Submission #520692

#	Time	Username	Problem	Language	Result	Execution time	Memory
520692		sidon	Three Friends (BOI14_friends)	C++17	100 / 100	13 ms	6168 KiB

friends

#include <bits/stdc++.h>
using namespace std;
 
string s;
int n;
 
bool match(int i, int j, int p = 0) {
	for(int k = 0; k <= n; k++)
		p += p < n && s[i+p] == s[j+k];
 
	return p == n;
}
 
int main() {
	ios::sync_with_stdio(0), cin.tie(0);
	cin >> n >> s;
 
	if(!(n & 1))
		return !(cout << "NOT POSSIBLE");
	n /= 2;
 
	bool L = match(0, n), R = match(n+1, 0);
 
	if(!L && !R) return !(cout << "NOT POSSIBLE");
	if(L && R && s.substr(0, n) != s.substr(n+1, n)) cout << "NOT UNIQUE";
	else cout << s.substr(R*(n+1), n);
}

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