제출 #1213670

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1213670		i_love_spring	Three Friends (BOI14_friends)	C++20	0 / 100	426 ms	132520 KiB

friends

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ar array
void solve() {  
    int n;
    cin >> n;
    string s;
    cin >> s;
    if (n % 2 == 0) {
      cout << "NOT POSSIBLE";
      return;
    }
    set<int> ans;
    set<ar<int,2>> bugs;
    for (int i = 0; i < n / 2;i++) {
      if (s[i] != s[i + n / 2 + 1]) bugs.insert({i, i + n / 2 + 1});
    }
    auto bl = bugs;
    auto br = bugs;
    for (int r  = n / 2; r < n - 1;r++) {
      int l = r - n / 2;
      if (s[l] != s[r + 1]) bl.erase({l,r + 1});
      if (s[l] != s[r]) bl.insert({l,r});
      if (bl.empty()) ans.insert(r + 1);
    }
    for (int l = n /2 - 1; l >= 0; l--) {
      int r = l + n / 2 + 1;
      if (s[l] != s[r]) br.erase({l,r});
      if (s[l + 1] != s[r]) br.insert({l + 1, r});
      if (br.empty()) ans.insert(l);
    }
    if (ans.size() > 1) cout << "NOT UNIQUE";
    else if (ans.empty()) cout << "NOT POSSIBLE";
    else {
      int cnt = 0,ok = 0;
      for (int i = 0; cnt < n / 2;i++) {
        if (ok == 0 && ans.count(i)) {
          ok = 1;
          continue;
        }
        cout << s[i];
        cnt++;
      }
    }
}
signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  cout.tie(nullptr);
  int t = 1;
  //cin >> t;
  while (t--) {
    solve();
    cout << "\n";
  }
  return 0;
} 

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