数据结构与算法：Binary search

//用JAVA实现折半查找

package com.java.algorithm;public class BinarySearch {public int binarySearch(int a[], int x) {   int left = 0, right = a.length - 1;   int mid = 0;   while (left <= right) {    mid = (left + right)/2;if (a[mid] < x){ left = mid + 1;} else if (a[mid] > x){right = mid - 1;}else{a[mid]=x;     break;   }  }return mid;  }public static void main(String[] args) {int [] arr = {1,2,3,4,5,6,7,8,9};BinarySearch bs = new BinarySearch();System.out.println("5的位置为："+bs.binarySearch(arr, 5)+",值为："+arr[bs.binarySearch(arr, 5)]);}}