java-算法设计与分析之二分搜索

package com.suanfa;public class BinarySearch {public static void main(String[] args){BinarySearch search=new BinarySearch();            System.out.print("利用二分搜索法得知x在该数组中的位置是："+search.backX(12));}public int backX(int x){int[] a={0,12,24,25,26,33,45,26};int left=0;int right=a.length-1;while(left<=right){int middle=(left+right)/2;if(x==a[middle]){                    return middle;}if(x>a[middle]){left=middle-1;}if(x<a[middle]){right=middle-1;}}return -1;}}