public class BinarySearch {public  static void main(String[] args){int[] array={1,5,8,11,19,22,31,35,40,45,48,49,50};int target=48;int idx=binarySearch(array,target);System.out.println();}//二分查找，找到返回元素索引，找不到返回-1public static int binarySearch(int[] a,int t){int l=0,r=a.length,m;while(l<=r){m=(l+r)/2;if(a[m]==t){return  m;}else if(a[m]>t){r=m-1;}else{l=m+1;}}return -1;}
}