Submission #653138

#	Time	Username	Problem	Language	Result	Execution time	Memory
653138		aryan12	Three Friends (BOI14_friends)	C++17	100 / 100	47 ms	6128 KiB

friends

#include <bits/stdc++.h>
using namespace std;
string s,t;
int l,r,i,p,n,f,g;

bool check() {
    p = 0;
    for(i = l; i <= r; i++) {
        if(p != t.size() && t[p] == s[i]) {
            p++;
        }
    }
    return (p == t.size());
}

int32_t main() {
    cin >> n;
    cin >> s;
    if(n % 2 == 0) {
        cout << "NOT POSSIBLE\n";
        return 0;
    }
    t = s.substr(0, n / 2);
    l = n / 2;
    r = n - 1;
    f = check();
    t = s.substr(n - n / 2, n / 2);
    l = 0;
    r = n / 2;
    g = check();
    if(!f && !g) {
        cout << "NOT POSSIBLE\n";
    }
    else if(f && g && s.substr(0, n / 2) != s.substr(n - n / 2, n / 2)) {
        cout << "NOT UNIQUE\n";
    }
    else if(f) {
        cout << s.substr(0, n / 2) << "\n";
    }
    else {
        cout << s.substr(n - n / 2, n / 2) << "\n";
    }
}

Compilation message (stderr)

friends.cpp: In function 'bool check()':
friends.cpp:9:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    9 |         if(p != t.size() && t[p] == s[i]) {
      |            ~~^~~~~~~~~~~
friends.cpp:13:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   13 |     return (p == t.size());
      |             ~~^~~~~~~~~~~

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