数组中出现次数超过一半的数字

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public class Solution {
    public int MoreThanHalfNum_Solution(int [] array) {
        if(array==null||array.length==0){
            return -1;
        }
        int start=0;
        int end=array.length-1;
        int index=partition(array,start,end);
        while(index<array.length/2){
            start=index+1;
            index=partition(array,start,end);
        }
        int result = array[array.length/2];         
        int times = 0;
        for(int i=0;i<array.length;++i){
            if(array[i] == result)
                times++;
        }
        if(times*2<=array.length){            
            return 0;
        }else{
            return result;
        }        
    }
    public int partition(int[] a,int low,int high) {
        int pivot = a[low];
        while (low < high) {
            while (low < high && a[high] >= pivot) {
                --high;
            }
            a[low]=a[high];
            while (low < high && a[low] <= pivot) {
                ++low;
            }
            a[high]=a[low];
        }
        a[low]=pivot;
        return low;
    }
}