Python (Simple Heap)
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time 
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```\nclass Solution:\n    def kSum(self, nums, k):\n        m = sum([i for i in nums if i > 0])\n        ans = [(-m,0)]\n        vals = sorted([abs(i) for i in nums])\n\n        for _ in range(k):\n            x,i = heapq.heappop(ans)\n            if i < len(vals):\n                heapq.heappush(ans,(x+vals[i],i+1))\n                if i: heapq.heappush(ans,(x-vals[i-1]+vals[i],i+1))\n\n        return -x\n```
['Python3']