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.

Example 1:

Input: [3,2,3]
Output: 3

Example 2:

Input: [2,2,1,1,1,2,2]
Output: 2

class Solution {
public:
    int majorityElement(vector& nums) {
        int j,candidate,count;                //candidate代表候选解即最多数元素，count代表票数
        for (j = 0; j < nums.size(); j++){
           candidate = nums[j]; count = 1;   //起初假定第一个元素即为candidate且票数为1，当票数count=0时就换candidate
           while (j < nums.size() - 1 && count>0){
                j = j + 1;
                if (nums[j] == candidate) count++;  //当下一个元素与candidate相等时票数+1
                else count--;                       //否则票数-1
             }
         }
        return candidate;
    }
};

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