CalcArea

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import static com.google.common.math.IntMath.mod;

public class Main {


    public static void main(String[] args) {
        Calculator calculator=new Calculator();

        int x = mod(7,3);
        System.out.println(x);

    }
}

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import java.util.Scanner;

public class Calculator {

    public Calculator() {
        //calc();
    }

    public void calc() {
        double area = 0;
        boolean flag = true;
        while (flag) {

            System.out.println("Calc Area:" +
                    "\n 1 - Circle" +
                    "\n 2 - Triangle" +
                    "\n 3 - Rectangle" +
                    "\n 4 - Other Regular Polygon" +
                    "\n 5 - Quit calculating");
            Scanner sc = new Scanner(System.in);
            int choice = sc.nextInt();
            if (choice == 1) {
                System.out.println("Enter radius (no units):");
                double radius = sc.nextDouble();
                area = calcArea(radius);
            } else if (choice == 2) {
                System.out.println("Enter side length 1:");
                double sideOne = sc.nextDouble();
                System.out.println("Enter side length 2:");
                double sideTwo = sc.nextDouble();
                System.out.println("Enter side length 1:");
                double sideThree = sc.nextDouble();
                area = calcArea(sideOne, sideTwo, sideThree);
            } else if (choice == 3) {
                System.out.println("Enter side length 1:");
                double sideOne = sc.nextDouble();
                System.out.println("Enter side length 2:");
                double sideTwo = sc.nextDouble();
                area = calcArea(sideOne, sideTwo);
            } else if (choice == 4) {
                System.out.println("Enter side length:");
                double sideLength = sc.nextDouble();
                System.out.println("Enter number of sides:");
                int sides = sc.nextInt();
                area = calcArea(sideLength, sides);
            } else {
                flag = false;
                break;
            }
            System.out.println("Area is: " + area);

        }
    }

    public double calcArea(double r) {
        double area = r * r * Math.PI;
        return area;
    }

    public double calcArea(double x, double y, double z) {
        double semiPerimeter = (x + y + z) / 2;
        double area = Math.sqrt((semiPerimeter - x) * (semiPerimeter - y) * (semiPerimeter - z) * (semiPerimeter));
        return area;
    }

    public double calcArea(double x, double y) {
        double area = x * y;
        return area;
    }

    public double calcArea(double x, int y) {
        double halfCentAngle = (360 / (y * 2))*Math.PI/180;
        double halfSide = x / 2;
        double apothem = halfSide / Math.tan(halfCentAngle);
        double area = x * y * apothem / 2;
        return area;
    }

}

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import org.junit.jupiter.api.Test;

import static org.junit.jupiter.api.Assertions.assertEquals;

public class CalculatorTests {
    Calculator calculator = new Calculator();

    @Test
    void test(){
        assertEquals(10,calculator.calcArea(5,2.0));
        //assertEquals(3.14,calculator.calcArea(1));
        //assertEquals(16,calculator.calcArea(4,4));
        assertEquals(16,calculator.calcArea(4,4.0));

    }
}

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