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"content": "<p>Given an array of <strong>distinct</strong> integers <code>candidates</code> and a target integer <code>target</code>, return <em>a list of all <strong>unique combinations</strong> of </em><code>candidates</code><em> where the chosen numbers sum to </em><code>target</code><em>.</em> You may return the combinations in <strong>any order</strong>.</p>\n\n<p>The <strong>same</strong> number may be chosen from <code>candidates</code> an <strong>unlimited number of times</strong>. Two combinations are unique if the frequency of at least one of the chosen numbers is different.</p>\n\n<p>It is <strong>guaranteed</strong> that the number of unique combinations that sum up to <code>target</code> is less than <code>150</code> combinations for the given input.</p>\n\n<p> </p>\n<p><strong>Example 1:</strong></p>\n\n<pre>\n<strong>Input:</strong> candidates = [2,3,6,7], target = 7\n<strong>Output:</strong> [[2,2,3],[7]]\n<strong>Explanation:</strong>\n2 and 3 are candidates, and 2 + 2 + 3 = 7. Note that 2 can be used multiple times.\n7 is a candidate, and 7 = 7.\nThese are the only two combinations.\n</pre>\n\n<p><strong>Example 2:</strong></p>\n\n<pre>\n<strong>Input:</strong> candidates = [2,3,5], target = 8\n<strong>Output:</strong> [[2,2,2,2],[2,3,3],[3,5]]\n</pre>\n\n<p><strong>Example 3:</strong></p>\n\n<pre>\n<strong>Input:</strong> candidates = [2], target = 1\n<strong>Output:</strong> []\n</pre>\n\n<p> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 <= candidates.length <= 30</code></li>\n\t<li><code>1 <= candidates[i] <= 200</code></li>\n\t<li>All elements of <code>candidates</code> are <strong>distinct</strong>.</li>\n\t<li><code>1 <= target <= 500</code></li>\n</ul>\n",
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"code": "class Solution {\npublic:\n vector<vector<int>> combinationSum(vector<int>& candidates, int target) {\n \n }\n};",
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"code": "class Solution(object):\n def combinationSum(self, candidates, target):\n \"\"\"\n :type candidates: List[int]\n :type target: int\n :rtype: List[List[int]]\n \"\"\"\n ",
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"code": "\n\n/**\n * Return an array of arrays of size *returnSize.\n * The sizes of the arrays are returned as *returnColumnSizes array.\n * Note: Both returned array and *columnSizes array must be malloced, assume caller calls free().\n */\nint** combinationSum(int* candidates, int candidatesSize, int target, int* returnSize, int** returnColumnSizes){\n\n}",
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