169. Majority Element

Given an array of size n, find the majority element. The majority element is the element that appears more than 

⌊
n/2 ⌋

 times.

You may assume that the array is non-empty and the majority element always exist in the array.

class Solution(object):
def majorityElement(self, nums):
"""
:type nums: List[int]
:rtype: int
"""
a=0
b=0
for i in nums:
if b==0:
a=i
b=1
else:
if a==i:
b+=1
else:
b-=1
return a