LeetCode（1-两数之和）（Python）

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解法一（7280 ms）：

class Solution:
    def twoSum(self, nums, target):
        """
        :type nums: List[int]
        :type target: int
        :rtype: List[int]
        """
        L = []
        for i in range(len(nums)):
            for j in range(i+1,len(nums)):
                if nums[i] + nums[j] == target:
                    L.append(i)
                    L.append(j)
                    return L  

解法二（896 ms ）：

class Solution(object):
    def twoSum(self, nums, target):
        """
        :type nums: List[int]
        :type target: int
        :rtype: List[int]
        """
        for i in range(len(nums)):
            if target-nums[i] in nums:
                idx=nums.index(target-nums[i])
                if idx!=i:
                    return [i,idx]

解法三（36ms）：

class Solution(object):
    def twoSum(self, nums, target):
        """
        :type nums: List[int]
        :type target: int
        :rtype: List[int]
        """
        dic={}
        for i in range(len(nums)):
            var=target-nums[i]
            if nums[i] in dic:
                return [dic[nums[i]],i]
            else:
                dic[var] = i