leetcode--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.

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1. public class Solution {  
2.     public int majorityElement(int[] nums) {  
3.         HashMap<Integer,Integer> map =new HashMap<Integer,Integer>();  
4.         int mid = nums.length/2;  
5.         for(int i = 0;i<nums.length;i++){  
6.             if(map.containsKey(nums[i])){  
7.                 int j = map.get(nums[i])+1;  
8.                 if(j>=mid) return nums[i];  
9.                 else map.put(nums[i], j);  
10.             }else{  
11.                 map.put(nums[i], 0);  
12.             }  
13.         }  
14.         return nums[0];  
15.     }  
16. }

原文链接http://blog.youkuaiyun.com/crazy__chen/article/details/46388301