Submission #713933

#	Time	Username	Problem	Language	Result	Execution time	Memory
713933		Stickfish	Three Friends (BOI14_friends)	C++17	0 / 100	1074 ms	4268 KiB

friends

#include <iostream>
#include <string>
#include <vector>
using namespace std;

signed main() {
    int n;
    cin >> n;
    string s;
    cin >> s;
    if (n % 2 == 0) {
        cout << "NOT POSSIBLE\n";
        return 0;
    }
    vector<int> ans;
    int m = n / 2;
    for (int i = 0; i < m; ++i) {
        if (s.substr(0, i) == s.substr(m + 1, i) && s.substr(i + 1, m - i) == s.substr(m + 1 + i, m - i))
            ans.push_back(i);
    }
    if (s.substr(0, m) == s.substr(m + 1, m))
        ans.push_back(m);
    for (int i = m + 1; i < n; ++i) {
        if (s.substr(m, i - m) == s.substr(0, i - m) && s.substr(i + 1, n - 1 - i) == s.substr(i - m, n - i - 1))
            ans.push_back(i);
    }
    if (ans.empty()) {
        cout << "NOT POSSIBLE\n";
        return 0;
    }
    for (size_t i = 0; i + 1 < ans.size(); ++i) {
        if (s.substr(ans[i], ans[i + 1]) != s.substr(ans[i] + 1, ans[i + 1] + 1)) {
            cout << "NOT UNIQUE\n";
            return 0;
        }
    }
    if (ans.size() > 1) {
        cout << "NOT UNIQUE\n";
        return 0;
    }
    s.erase(s.begin() + ans[0]);
    cout << s.substr(0, n / 2);
}

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