leetcode-39-Combination Sum

Given a set of candidate numbers (candidates) (without duplicates) and a target number (target), find all unique combinations in candidates where the candidate numbers sums to target.

The same repeated number may be chosen from candidates unlimited number of times.

Note:

All numbers (including target) will be positive integers.

The solution set must not contain duplicate combinations.

Example 1:

Input: candidates = [2,3,6,7], target = 7,
A solution set is:
[
  [7],
  [2,2,3]
]

Example 2:

Input: candidates = [2,3,5], target = 8,
A solution set is:
[
  [2,2,2,2],
  [2,3,3],
  [3,5]
]

class Solution {
    public List<List<Integer>> combinationSum(int[] candidates, int target) {
        List<List<Integer>> result = new ArrayList<List<Integer>>();
        comb(result, candidates, 0, new ArrayList<Integer>(), target);
        return result;
    }
    public void comb(List<List<Integer>> result, int[] candidates, int minIndex, List<Integer> path, int target)
    {
        if(target < 0)
            return;
        else if(target == 0)
            result.add(path);
        else
        {
            for(int i=minIndex; i<candidates.length; i++)
            {
                List<Integer> newPath = new ArrayList(path);
                newPath.add(candidates[i]);
                comb(result, candidates, i, newPath, target-candidates[i]);
            }
        }
            
    }
}