JAVA 二分查找代码_二分查找的java代码

自己留着看

public class BinarySearch {
    public static void main(String[] args) {
        int[] bs ={1,3,5,7,9,13,17,20,33,37};
        int low=0,mid;
        int high=bs.length-1;
        int m=10;     //需要找的数
        int count=0; //比较的次数
        while(low<=high)
        {
            mid=(low+high)/2;
            if(m<bs[mid])
            {
                high=mid-1;   //注意！！high=mid-1，以前忘了
                count++;
            }
            else if (m>bs[mid])
            {
                low= mid+1;  //注意！！low= mid+1，以前忘了
                count++;
            }
            else {
                count++;
                System.out.println("找到了,下标是" + mid + "比较了" + count);
                break;
            }
        }
        if(low>high)
        {
            System.out.println("未找到"+"比较了" + count);
        }
    }
}

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