Question

.
Write a program in Java to display the following choice to the user:
1. Area of Square
2. Area of Rectangle
3.Area of Circle
And as per user's choice using if statements (only) calculate the area of square, rectangle or circle taking
necessary inputs inside the respective if statements.​

Answer 1

Explanation:

Area of square

1) Program 1: Prompting user for entering the side of the square

2) Program 2: Side of the square is specified in the program’ s source code.

Program 1:

/**

* @author: BeginnersBook.com

* @description: Program to Calculate Area of square.Program

* will prompt user for entering the side of the square.

*/

import java.util.Scanner;

class SquareAreaDemo {

public static void main (String[] args)

{

System.out.println("Enter Side of Square:");

//Capture the user's input

Scanner scanner = new Scanner(System.in);

//Storing the captured value in a variable

double side = scanner.nextDouble();

//Area of Square = side*side

double area = side*side;

System.out.println("Area of Square is: "+area);

}

}

Output:

Enter Side of Square:

2.5

Area of Square is: 6.25

Program 2:

/**

* @author: BeginnersBook.com

* @description: Program to Calculate Area of square.

* No user interaction: Side of square is hard-coded in the

* program itself.

*/

class SquareAreaDemo2 {

public static void main (String[] args)

{

//Value specified in the program itself

double side = 4.5;

//Area of Square = side*side

double area = side*side;

System.out.println("Area of Square is: "+area);

}

}

Output:

Area of Square is: 20.25