text: METHOD = "twoSum"
  
  TESTCASES = [
      ([2,7,11,15],9),
      ([-1,-2,-3,-4,-5],-8)
  ]
  
  class Solution:
      def twoSum(self, nums, target):
          """
          :type nums: List[int]
          :type target: int
          :rtype: List[int]
          """
          mem = {}
          for i in range(len(nums)):
              x = nums[i]
              y = target - x
              if y in mem:
                  return [i,mem[y]]
              mem[x] = i