题目描述

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.

Credits:

Special thanks to @ts for adding this problem and creating all test cases.

分析

参考：A Linear Time Majority Vote Algorithm

一个典型的算法，可以在一次遍历，时间复杂度是O(1)，空间复杂度是O(1)的情况下完成。

代码

    public static int majorityElement(int[] nums) {

        int m = nums[0];
        int c = 1;

        for (int i = 1; i < nums.length; i++) {
            if (m == nums[i]) {
                c++;
            } else if (c > 1) {
                c--;
            } else {
                m = nums[i];
            }
        }

        return m;
    }