combinations in java
private void helper(List<int[]> combinations, int data[], int start, int end, int index) { if (index == data.length) { int[] combination = data.clone(); combinations.add(combination); } else if (start <= end) { data[index] = start; helper(combinations, data, start + 1, end, index + 1); helper(combinations, data, start + 1, end, index); } }
