折半查找

折半

public class MidSearch {public static void main(String[] args){ int a[]={1,4,6,9,12}; int i=search(a,0,a.length-1,6); System.out.println(i); }public static  int search(int a[],int low,int high,int key){   int mid=(low+high)/2;if (a[mid]==key)return mid;else if (a[mid]>key)return search(a,0,mid-1,key);else return search(a,mid+1,high,key); }}