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# 40. Combination Sum II

## Medium

***

Given a collection of candidate numbers (`candidates`) and a target number (`target`), find all unique combinations in `candidates` where the candidate numbers sum to `target`.

Each number in `candidates` may only be used **once** in the combination.

**Note:** The solution set must not contain duplicate combinations.

 

**Example 1:**

```
Input: candidates = [10,1,2,7,6,1,5], target = 8
Output: 
[
[1,1,6],
[1,2,5],
[1,7],
[2,6]
]
```

**Example 2:**

```
Input: candidates = [2,5,2,1,2], target = 5
Output: 
[
[1,2,2],
[5]
]
```

 

**Constraints:**

* `1 <= candidates.length <= 100`
* `1 <= candidates[i] <= 50`
* `1 <= target <= 30`