题解 | #数组中只出现一次的数（其它数出现k次）#

class Solution:
    def foundOnceNumber(self , arr , k ):
        # write code here
        b = sorted(arr)
        i = 0
        while i <len(b)-1:
            if b[i] == b[i+1]:
                i += k
            else:
                return b[i]
        return b[-1]