comefrom: <gouthampradhan>backtracking_Permutations_1.java
code: private void nextPermutation(int i, int[] nums, List<List<Integer>> result) {
      if (i == nums.length - 1) {
        List<Integer> list = new ArrayList<>();
        for (int n : nums) list.add(n);
        result.add(list);
      } else {
        for (int j = i, l = nums.length; j < l; j++) {
          int temp = nums[j];
          nums[j] = nums[i];
          nums[i] = temp;
          nextPermutation(i + 1, nums, result);
          temp = nums[j];
          nums[j] = nums[i];
          nums[i] = temp;
        }
      }
    }
masked: private void sample_funcname ( int i , int [ ] nums , List < List < Integer >> result ) {
    if ( i == nums . length - 1 ) {
      List < Integer > list = new ArrayList < > ( ) ;
      for ( int n : nums ) list . add ( n ) ;
      result . add ( list ) ;
    }
    else {
      for ( int j = i , l = nums . length ;
      j < l ;
      j ++ ) {
        int temp = nums [ j ] ;
        nums [ j ] = nums [ i ] ;
        nums [ i ] = temp ;
        nextPermutation ( i + 1 , nums , result ) ;
        temp = nums [ j ] ;
        nums [ j ] = nums [ i ] ;
        nums [ i ] = temp ;
      }
    }
  }
  