# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
653134 | aryan12 | Three Friends (BOI14_friends) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
#define int long long
mt19937_64 RNG(chrono::steady_clock::now().time_since_epoch().count());
string s, t;
int l, r, i, pos, n;
bool f1, f2;
bool check(string t, int l, int r) {
int pos = 0;
for(i = l; i <= r; i++) {
if(pos != t.size() && t[pos] == s[i]) {
pos++;
}
}
return (pos == t.size());
}
void Solve() {
cin >> n;
cin >> s;
if(n % 2 == 0) {
cout << "NOT POSSIBLE\n";
return;
}
t = s.substr(0, n / 2);
l = n / 2;
r = n - 1;
f1 = check();
t = s.substr(n - n / 2, n / 2);
l = 0;
r = n / 2;
f2 = check();
if(!f1 && !f2) {
cout << "NOT POSSIBLE\n";
}
else if(f1 && f2 && s.substr(0, n / 2) != s.substr(n - n / 2, n / 2)) {
cout << "NOT UNIQUE\n";
}
else if(f1) {
cout << s.substr(0, n / 2) << "\n";
}
else {
cout << s.substr(n - n / 2, n / 2) << "\n";
}
}
int32_t main() {
auto begin = std::chrono::high_resolution_clock::now();
ios_base::sync_with_stdio(0);
cin.tie(0);
int t = 1;
//cin >> t;
while(t--) {
Solve();
}
auto end = std::chrono::high_resolution_clock::now();
auto elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(end - begin);
cerr << "Time measured: " << elapsed.count() * 1e-9 << " seconds.\n";
return 0;
}