SquareRoot.java

import java.util.Scanner;

public class SquareRoot {

 public static void main (String args[]) {

 Scanner in = new Scanner(System.in);
 System.out.println("Please enter a number : ");

 int val = in.nextInt();

 //loops until user gives a valid number
 while (val <= 0) {
 System.out.println("Please enter a value greater than 0");
 val = in.nextInt();
 }
 double valCopy;

 double squareRoot = val / 2;

 valCopy = squareRoot;
 squareRoot = (valCopy + (val / valCopy)) / 2;

 // Uses a loop comparing our value to its root. The loop will become false when
 // square root next value is our inputted number
 while (true) {
 if ((valCopy - squareRoot) == 0) break;
 valCopy = squareRoot;
 squareRoot = (valCopy + (val / valCopy)) / 2;
 }

 System.out.printf("Square root of %d is %.1f", val, squareRoot);
 }

}