Submission #146286

#	Time	Username	Problem	Language	Result	Execution time	Memory
146286		meatrow	Three Friends (BOI14_friends)	C++17	100 / 100	20 ms	7324 KiB

friends

#pragma GCC optimize("O3")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,tune=native")
//#pragma GCC optimize ("unroll-loops")
#include <bits/stdc++.h>
 
using namespace std;
 
using ll = long long;
using ld = long double;


int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int n;
    string s;
    cin >> n >> s;
    if (n % 2 == 0) {
        cout << "NOT POSSIBLE";
        return 0;
    }
    string a = s.substr(0, n / 2);
    string b = s.substr(n / 2 + 1);
    int i = 0;
    for (int j = n / 2; j < n; j++) {
        if (i < n / 2 && s[j] == a[i]) {
            i++;
        }
    }
    int cnt = 0;
    int first = 0;
    if (i == n / 2) {
        cnt++;
        first = 1;
    }
    i = 0;
    for (int j = 0; j <= n / 2; j++) {
        if (i < n / 2 && s[j] == b[i]) {
            i++;
        }
    }
    if (i == n / 2) {
        cnt++;
    }
    if (!cnt) {
        cout << "NOT POSSIBLE";
    }
    if (cnt == 1) {
        if (first) {
            cout << a;
        } else  {
            cout << b;
        }
    }
    if (cnt == 2) {
        if (a == b) {
            cout << a;
        } else {
            cout << "NOT UNIQUE";
        }
    }
    return 0;
}

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