Combination Sum II
Given a collection of candidate numbers (candidates
) and a target number (target
), find all unique combinations in candidates
where the candidate numbers sums to target
.
Each number in candidates
may only be used once in the combination.
Note:
All numbers (including
target
) will be positive integers.The solution set must not contain duplicate combinations.
Example 1:
Input: candidates = [10,1,2,7,6,1,5], target = 8,
A solution set is:
[
[1, 7],
[1, 2, 5],
[2, 6],
[1, 1, 6]
]
Example 2:
Input: candidates = [2,5,2,1,2], target = 5,
A solution set is:
[
[1,2,2],
[5]
]
class Solution {
public List<List<Integer>> combinationSum2(int[] nums, int target) {
List<List<Integer>> list = new ArrayList<>();
Arrays.sort(nums);
backtrack(list, new ArrayList<>(), nums, target, 0);
return list;
}
private void backtrack(List<List<Integer>> list, List<Integer> temp, int[] nums, int target, int start) {
if (target <= 0) {
if (target == 0)
list.add(new ArrayList<>(temp));
return;
}
for (int i = start; i < nums.length; i++) {
if (i > start && nums[i] == nums[i - 1])
continue; // skip duplicates
temp.add(nums[i]);
backtrack(list, temp, nums, target - nums[i], i + 1);
temp.remove(temp.size() - 1);
}
}
}
Last updated