编辑代码

public class Test {
    public static void main(String []args) {
        int[] arr = new int[]{-21, 2, 32, 43,53, 90};
        int dest =20;
        int low = 0,high = arr.length - 1;
        boolean flag = true;
        while(low <= high){
            int middle = (low + high)/2;
            if(dest==arr[middle]){
                System.out.println("找到了");
                flag = false;
                break;
            }else if(dest < arr[middle]){
                high = middle - 1;
            }else{
                low = middle + 1;
            }
        }
        if(flag){
            System.out.println("找不到");
        }
    }
}