import java.util.HashMap; public class Solution { public int MoreThanHalfNum_Solution(int [] array) { if(array==null||array.length==0)return 0; HashMap<Integer,Integer> m = new HashMap<Integer,Integer>(); for(int i=0;i<array.length;i++){ if(!m.containsKey(array[i]))m.put(array[i],1); else m.put(array[i],m.get(array[i])+1); } //注意此处返回key for(int key: m.keySet()){ if(m.get(key)>array.length/2) return key; } return 0; } }