comefrom: <gouthampradhan>bit_manipulation_BinaryWatch_1.java
code: public List<String> readBinaryWatch(int num) {
      int H = 11, M = 59;
      List<String> result = new ArrayList<>();
      if (num == 0) {
        result.add("0:00");
        return result;
      }
      for (int i = 0; i <= H; i++) {
        for (int j = 0; j <= M; j++) {
          int count = 0;
          for (int k = 0; k < 4; k++) {
            if (((1 << k) & i) > 0) {
              count++;
            }
          }
          for (int k = 0; k < 6; k++) {
            if (((1 << k) & j) > 0) {
              count++;
            }
          }
          if (count == num) {
            result.add(i + ":" + ((String.valueOf(j).length() == 1) ? ("0" + j) : j));
          }
        }
      }
      return result;
    }
masked: public List < String > var_1 ( int var_2 ) {
    int var_4 = 11 , var_6 = 59 ;
    List < String > var_9 = new ArrayList < > ( ) ;
    if ( var_2 == 0 ) {
      var_9 . add ( "0:00" ) ;
      return var_9 ;
    }
    for ( int var_13 = 0 ;
    var_13 <= var_4 ;
    var_13 ++ ) {
      for ( int var_14 = 0 ;
      var_14 <= var_6 ;
      var_14 ++ ) {
        int var_15 = 0 ;
        for ( int var_16 = 0 ;
        var_16 < 4 ;
        var_16 ++ ) {
          if ( ( ( 1 << var_16 ) & var_13 ) > 0 ) {
            var_15 ++ ;
          }
        }
        for ( int var_16 = 0 ;
        var_16 < 6 ;
        var_16 ++ ) {
          if ( ( ( 1 << var_16 ) & var_14 ) > 0 ) {
            var_15 ++ ;
          }
        }
        if ( var_15 == var_2 ) {
          var_9 . add ( var_13 + ":" + ( ( String . valueOf ( var_14 ) . length ( ) == 1 ) ? ( "0" + var_14 ) : var_14 ) ) ;
        }
      }
    }
    return var_9 ;
  }
  