comefrom: <awangdev>168. Excel Sheet Column Title_1.java
code: public String convertToTitle(int n) {
          if (n <= 0) {
              return null;
          }
          
          StringBuilder sb = new StringBuilder();
          while (n > 0) {
              int remain = n % 26;
              n = n / 26;
              if (remain == 0) {
                  sb.append("Z");
                  n--;
              } else {
                  sb.append((char)('A' + remain - 1));
              }
          }
          return sb.reverse().toString();
      }
masked: public String var_0 ( int var_1 ) {
    if ( var_1 <= 0 ) {
      return null ;
    }
    StringBuilder var_2 = new StringBuilder ( ) ;
    while ( var_1 > 0 ) {
      int var_3 = var_1 % 26 ;
      var_1 = var_1 / 26 ;
      if ( var_3 == 0 ) {
        var_2 . append ( "Z" ) ;
        var_1 -- ;
      }
      else {
        var_2 . append ( ( char ) ( 'A' + var_3 - 1 ) ) ;
      }
    }
    return var_2 . reverse ( ) . toString ( ) ;
  }
  