Python Hash Table 961. N-Repeated Element in Size 2N Array

leetcode 961.2N数组中的N重复元素

算法思想：因为题中描述为除了重复元素，其余均为非重复元素，则遇到重复元素则为所求。

代码：

class Solution(object):
    def repeatedNTimes(self, A):
        """
        :type A: List[int]
        :rtype: int
        """
        length = len(A);
        i = 0; 
        while i<length:
            j = i+1;
            while j<length:
                if A[i] == A[j]:
                    return A[i];
                j = j+1;
            i = i+1;