連結

167. Two Sum II - Input Array Is Sorted
https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/

一開始思考方向不能是從前面慢慢找，因為是有排序的，而且會有重複的，所以可以使用從頭尾找的方式

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class Solution(object):
    def twoSum(self, numbers, target):
        start_point=0
        end_point=-1
        for index, val in enumerate(numbers):
            if target < numbers[start_point]+numbers[end_point]:
                end_point-=1
            elif target > numbers[start_point]+numbers[end_point]:
                start_point+=1
        return start_point+1,len(numbers)+end_point+1

神人解答

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class Solution(object):
    def twoSum(self, numbers, target):
        dic = {}
        for i, n in enumerate(numbers):
            if n in dic:
                return [dic[n]+1, i+1]
            dic[target-n] = i