leetcode 169

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.

找出数列中个数超过一半的数，假定数列不为空且该数一定存在。

代码如下：

class Solution {
public:
    int majorityElement(vector<int>& nums) {
        int n = nums.size();
        int index = 0;
        int candidate = nums[0];
        for(int i = 0; i < n; i++)
        {
            if(candidate == nums[i])
            {
                index ++;
            }
            else
            {
                index --;
            }
            if(index < 0)
            {
                candidate = nums[i];
                index = 0;
            }
        }
        return candidate;
    }
};