https://leetcode.com/problems/two-sum
Given an array of integers, return indices of the two numbers such that they add up to a specific target.
You may assume that each input would have exactly one solution, and you may not use the same element twice.
Example:
Given nums = [2, 7, 11, 15], target = 9,
Because nums[0] + nums[1] = 2 + 7 = 9, return [0, 1].
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class Solution: def twoSum(self, nums, target): """ :type nums: List[int] :type target: int :rtype: List[int] """ for i in range(len(nums)): for j in range(i+1, len(nums)): if nums[i] + nums[j] == target: return i,j
class Solution: def twoSum(self, nums, target): """ :type nums: List[int] :type target: int :rtype: List[int] """ lookup = {} for i,num in enumerate(nums): if target - num in lookup: return lookup[target-num],i else: lookup[num] = i