Submission #3458585

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;

int main() {
  int N;
  string S;
  cin >> N >> S;
  if (N % 2 == 0) {
    cout << -1 << endl;
    return 0;
  }

  int ans = N / 2;
  for (int i = 0; i <= ans; i++) {
    char f, e;
    if (i % 3 == 0) {
      f = 'b'; e = 'b';
    } else if (i % 3 == 1) {
      f = 'a'; e = 'c';
    } else {
      f = 'c'; e = 'a';
    }
    if (S[ans-i] != f || S[ans+i] != e) {
      cout << -1 << endl;
      return 0;
    }
  }
  cout << ans << endl;
}

Submission Info

Judge Result