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Area of a Circle without new Class and Math Class-Example0009

Area of a Circle without new Class and Math Class-Example0009
This example is example for using Scanner class to get input from user and calculate area of a circle.
Using of Class Math is also shown
Also casting from double to float is also shown
package com.swprogramdeveloper;

Keyword: java, aoc, scanner, user input, casting, math class

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
// write your code here
        final float PI=3.14F;
        Scanner askinput= new Scanner(System.in);
        System.out.print("Please Enter Radius of the Circle:");
        float radius= askinput.nextFloat();

        //Using Mathematical expression
        float area= PI * radius * radius;
        System.out.print("Area of Circle(PIXRXR):");
        System.out.println(area);

        //Using Math Class
        //Need Explicit Casting- Casting: changing types from double to float- Math.pow returns double
        float area1= PI * (float)Math.pow(radius,2);
        System.out.print("Area of Circle(Using Math Class for Power(PIXR*2):");
        System.out.println(area1);
    }
}


Output0009
==========

Please Enter Radius of the Circle:7
Area of Circle(PIXRXR):153.86002
Area of Circle(Using Math Class for Power(PIXR*2):153.86

Process finished with exit code 0

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