Submission #62449

#	Time	Username	Problem	Language	Result	Execution time	Memory
62449		RezwanArefin01	Three Friends (BOI14_friends)	C++17	100 / 100	136 ms	24524 KiB

friends

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> ii; 

string s; 
set<string> st; 

void match(int l1, int r1, int l2, int r2) {
	bool flag = 0; string x = ""; 
	while(l1 <= r1) {
		if(s[l1] != s[l2]) {
			if(flag) return; 
			flag = 1; --l1; 
		} else x += s[l1];  
		++l1, ++l2; 
	} 
	if(flag || (l2 <= r2 && !flag)) 
		st.insert(x); 
}
int main(int argc, char const *argv[]) {
	int n; cin >> n >> s; 
	if(~n & 1) return 0*puts("NOT POSSIBLE");
	int x = n >> 1; 
	match(0, x - 1, x, n - 1);
	match(x + 1, n - 1, 0, x); 

	if(!st.size()) puts("NOT POSSIBLE"); 
	else if(st.size() > 1) puts("NOT UNIQUE"); 
	else cout << *st.begin() << endl; 
}

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