leetcode

Missing Number

Missing Number

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class Solution(object):
    def missingNumber(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        return (set([x for x in xrange(len(nums) + 1)]) - set(nums)).pop()
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class Solution(object):
    def missingNumber(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        n = len(nums)
        return n * (n+1) / 2 - sum(nums)

test code

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In [135]: s = Solution(); t = s.missingNumber([9,6,4,2,3,5,7,0,1])
In [136]: t
Out[136]: 8

leet code