算法打卡-day9

递归二分查找

public class E03BinarySearch {

    public static int search(int[] a,int target){
        return f(a,target,0,a.length-1);
    }
    public static void main(String[] args) {

    }

    //i为起始索引
    private static int f(int[] a,int target,int i,int j){
        //出口
        if(i>j){
            return -1;
        }
        int m=(i+j)>>1;
        if(targeta[m]){
            return f(a,target,m+1,j);
        }else{
            return m;
        }
    }
}