1. Introduction

A perfect square is a number that can be expressed as the product of an integer with itself. For example, 1, 4, 9, and 16 are perfect squares, but 8 and 14 are not. In this blog post, we will create a Java program that checks whether a given number is a perfect square.

2. Program Steps

1. Define a class named PerfectSquare.

2. Inside the main method, initialize a variable num with the number to be checked.

3. Calculate the square root of num and store it in a variable sqrt.

4. Check whether the square of sqrt is equal to num.

5. If it is, print that num is a perfect square; otherwise, print that it is not.

3. Code Program

public class PerfectSquare { // Step 1: Define a class named PerfectSquare

    public static void main(String[] args) { // Main method

        int num = 25; // Step 2: Initialize variable num with the number to be checked

        // Step 3: Calculate the square root of num and store it in variable sqrt
        int sqrt = (int) Math.sqrt(num);

        // Step 4: Check whether the square of sqrt is equal to num
        if (sqrt * sqrt == num) {
            // Step 5: Print that num is a perfect square
            System.out.println(num + " is a perfect square.");
        } else {
            // Print that num is not a perfect square
            System.out.println(num + " is not a perfect square.");
        }
    }
}

Output:

25 is a perfect square.

4. Step By Step Explanation

– Step 1: A class named PerfectSquare is defined.

– Step 2: Inside the main method, a variable num is initialized with the number to be checked.

– Step 3: The square root of num is calculated using Math.sqrt() method and the result is stored in a variable sqrt. The value is cast to int to compare it with num later.

– Step 4: The program checks whether the square of sqrt is equal to num.

– Step 5: Depending on the condition in Step 4, the program prints whether num is a perfect square or not.