x的平方根

在不使用sqrt(x)函数的情况下，得到x的平方根的整数部分

public class SqrtX {
    public static void main(String[] args) {
        System.out.println(binarySearch(24));
        System.out.println(newton(24));
    }
    //二分查找
    public static int binarySearch(int x){
        int index = -1,l = 0,r = x;
        while (l<=r){
            int mid = l+(r-l)/2;
            if (mid*mid <=x){
                index = mid;
                l = mid+1;
            }else {
                r = mid-1;
            }
        }
        return index;
    }
    //牛顿迭代
    public static int newton(int x){
        if(x==0){
            return 0;
        }
        return (int)sqrt(x,x);
    }
    public static double sqrt(double i,int x){
        double res = (i+x/i)/2;
        if (res == i){
            return I;
        }else{
            return sqrt(res,x);
        }

    }
}