leetcode 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

找到个数超过一半的数
思路：对数组排序， 如果nums[i]==nums[i+l/2] 则表示这个数是众数

#include<algorithm>
class Solution {
public:
    int majorityElement(vector<int>& nums) {
        sort(nums.begin(), nums.end());
        int l=nums.size(), flag=true, ans;
        for(int i=0; i<=l/2 && flag; i++){
            if(nums[i+l/2]==nums[i]){
                flag=0;
                ans=nums[i];
            }
        }
        return ans;
    }
};