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.
给定一个数组，找这个数组中的主元素，主元素是元素出现次数大于? n/2 ?的元素。 假设给定的数组非空，主元素都存在。
1 public int majorityElement(int[] nums) { 2 Map<Integer, Integer> numberMap = new HashMap<>(); 3 for (int i = 0; i < nums.length; i++) { 4 numberMap.put(nums[i], numberMap.getOrDefault(nums[i], 0)+1); 5 } 6 int level = (nums.length+1)/2; 7 for (Map.Entry<Integer, Integer> e : numberMap.entrySet()) { 8 if (e.getValue() >= level) { 9 return e.getKey(); 10 } 11 } 12 return Integer.MIN_VALUE; 13 }
原文：http://www.cnblogs.com/wzj4858/p/7668617.html