Combination Sum II

Problem Statement

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.

LeetCode link

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

Code

Python Code

class Solution(object):
    def combinationSum2(self, candidates, target):
        candidates.sort()
        table = [None] + [set() for i in range(target)]
        for i in candidates:
            if i > target:
                break
            for j in range(target - i, 0, -1):
                table[i + j] |= {elt + (i,) for elt in table[j]}
            table[i].add((i,))
        return map(list, table[target])