BigInteger sqrtAndRemainder() Method in Java with Examples

The java.math.BigInteger.sqrtAndRemainder() method performs an operation upon the current BigInteger by which this method is called. This method is used to calculate the integer square root (sqrt(this)) of this number and the remainder of this number with the square. It returns an array of two BigIntegers containing the integer square root ‘p’ of this and its remainder (this – p*p), respectively. BigInteger class internally uses an array of integers for processing, so the operation on an object of BigIntegers is not as fast as on primitives.

Note: This method is available since JDK 9

Syntax:

public BigInteger[] sqrtAndRemainder()

Parameters: This method accepts no parameter.

Return Value: This method returns an array of two BigIntegers with the integer square root at index 0 and the remainder at index 1.

Exception: The number must be positive otherwise ArithmeticException is thrown.

Below programs illustrate sqrtAndRemainder() method of BigInteger class

Example 1:

// Java program to demonstrate
// sqrtAndRemainder() method of BigInteger

import java.math.BigInteger;

class Main {
    public static void main(String[] args)
    {
        // BigInteger object to store result
        BigInteger res[];

        // For user input
        // Use Scanner or BufferedReader

        // Two object of String created
        // Holds the values to perform operation
        String input1 = "15";

        // Convert the string input to BigInteger
        BigInteger a
            = new BigInteger(input1);

        // Using sqrtAndRemainder() method
        try {

            res = a.sqrtAndRemainder();

            // Display the result
            System.out.println("The square root of\n"
                               + a + "\nis " + res[0]
                               + "\nand remainder is "
                               + res[1]);
        }
        catch (ArithmeticException e) {
            System.out.println(e);
        }
    }
}

Output:

The square root of
15
is 3
and remainder is 6

Example 2:

// Java program to demonstrate
// sqrtAndRemainder() method of BigInteger

import java.math.BigInteger;

class Main {
    public static void main(String[] args)
    {
        // BigInteger object to store result
        BigInteger res[];

        // For user input
        // Use Scanner or BufferedReader

        // Two object of String created
        // Holds the values to perform operation
        String input1 = "625";

        // Convert the string input to BigInteger
        BigInteger a
            = new BigInteger(input1);

        // Using sqrtAndRemainder() method
        try {

            res = a.sqrtAndRemainder();

            // Display the result
            System.out.println("The square root of\n"
                               + a + "\nis " + res[0]
                               + "\nand remainder is "
                               + res[1]);
        }
        catch (ArithmeticException e) {
            System.out.println(e);
        }
    }
}

Output:

The square root of
625
is 25
and remainder is 0

Example 3:
Program showing exception when value is negative.

// Java program to demonstrate
// sqrtAndRemainder() method of BigInteger

import java.math.BigInteger;

class Main {
    public static void main(String[] args)
    {
        // BigInteger object to store result
        BigInteger res[];

        // For user input
        // Use Scanner or BufferedReader

        // Two object of String created
        // Holds the values to perform operation
        String input1 = "-9";

        // Convert the string input to BigInteger
        BigInteger a
            = new BigInteger(input1);

        // Using sqrtAndRemainder() method
        try {

            res = a.sqrtAndRemainder();

            // Display the result
            System.out.println("The square root of\n"
                               + a + "\nis " + res[0]
                               + "\nand remainder is "
                               + res[1]);
        }
        catch (ArithmeticException e) {
            System.out.println(e);
        }
    }
}

Output:

java.lang.ArithmeticException: Negative BigInteger

References: https://docs.oracle.com/javase/9/docs/api/java/math/BigInteger.html#sqrtAndRemainder–