leetcode刷题

#20181205
class Solution:
    def twoSum(self,nums, target):
        """
        :type nums: List[int]
        :type target: int
        :rtype: List[int]
        """
        n = len(nums)
        d = {}
        for i in range(n):
            a = target - nums[i]
            if nums[i] in d:
                return d[nums[i]], i
            else:
                d[a] = i

#20181206
class Solution:
    def reverse(self, x):
        """
        :type x: int
        :rtype: int
        """
        reverse_x = ""
        sign = ""
        if x < 0:
            x = -x
            sign = "-"
        for i in str(x):
            reverse_x = i + reverse_x
        reverse_x = sign + reverse_x
        if int(reverse_x) < pow(-2, 31) or int(reverse_x) > pow(2, 31) - 1:
            return 0
        return int(reverse_x)