找出数组中唯一的重复元素

def findDup(array):
    hashTable = dict()
    for i in range(len(array)):
        try:
            hashTable[array[i]]
            return array[i]
        except:
            hashTable[array[i]] = 0
    return -1

if __name__ == '__main__':
    array = [1, 8, 4, 2, 5, 3, 3]
    print(findDup(array))