Java won't print output

Question

I'm using binary search to write a simple square root calculator that takes in doubles in Java. When I tried to test my code by printing out the answer in the main function, however, nothing got printed out in the terminal. I also got errors Possible lossy conversion from double to float...... Here is my code:

public class MyMath{
    public static double sqrt(double n){
        double u = 1;
        double l = 0;
        float m = (u + l) / 2;
        double norm_input = 1;
        float acc = 0.00000000001;
        double answer = 0;
        if ((n > 0) && (n < 1)){
            if ((m * m) < n){
                l = m;
            }else{
                u = m;
            }
            answer = (u + l) / 2;
            return answer;
        }else{
            int count = 0;
            while (n > 1){
                n = n / 4;
                norm_input = norm_input * 2;
                count++;
            }
            while ((u - l) > acc){
                if ((m * m) < n){
                    l = m;
                }else{
                    u = m;
                }
            }
            answer = (u + l) / 2 * norm_input;
            return answer;
        }
    }
    public static void main(String[] args){
        double a = new MyMath().sqrt(4);
        System.out.println(a);
    }
}

Answer 1

float m = (u + l) / 2;
Here you have to type cast into float because when two datatype variable participated in division the result would be in higher data type.

float acc = 0.00000000001;
Here also you have type cast because by default java treats a decimal point value as Double.

while ((u - l) > acc){
    if ((m * m) < n){
        l = m;
    }
}

and your code here is going to infinite loop .

Answer 2

It is stuck in infinite loop in second while condition, that's the reason it is not printing values to console.