title: Perfect Reversible String
signature: function perfectReversibleString($str) {
source_py: def perfect_reversible_string(str):
      i = 0
      j = (len(str) - 1)
      while (i < j):
          if (str[i] != str[j]):
              return False
          i += 1
          j -= 1
      return True
source_cpp: bool perfect_reversible_string(string str) {
    int i = 0, j = str . length ( ) - 1;
    while ( i < j ) {
      if ( str [ i ] != str [ j ] ) return false;
      i ++;
      j --;
    }
    return true;
  }