Practice 02: Operators in Java

1.Write a program to implement arithmetic operators.

public class j04ArithmeticOperators {
    public static void main(String[] args) {
        // declare variables
        int a = 12, b = 5;

        // addition operator
        System.out.println("a + b = " + (a + b));
        // subtraction operator
        System.out.println("a - b = " + (a - b));
        // multiplication operator
        System.out.println("a * b = " + (a * b));
        // division operator
        System.out.println("a / b = " + (a / b));
        // modulo operator
        System.out.println("a % b = " + (a % b));
    }
}

2.Write a program to add three numbers and find their sum and mean.

import java.util.Scanner;

public class j05threenumsummean {
    public static void main(String[] args) {
        int a, b, c;
        int sum;
        double mean;
        Scanner sc = new Scanner(System.in);

        System.out.println("Enter three numbers: ");
        a = sc.nextInt();
        b = sc.nextInt();
        c = sc.nextInt();
        sum = a+b+c;
        System.out.println("Sum is: "+sum);

        mean = sum/3.0;

        System.out.println("Mean is: "+mean);
    }
}

3.Write a program to read a radius of a circle and find its area and circumference.

import java.util.Scanner;

public class j06radiusofcircle {
    public static void main(String[] args) {
        int r;
        double a,c;
        System.out.println("Enter radius of circle: ");
        Scanner sc = new Scanner(System.in);
        r = sc.nextInt();

        a = 3.14*r*r;
        System.out.println("Area of circle is: "+a);

        c = 3.14*2*r;
        System.out.println("Circumference of circle is: "+c);
    }
}

4.Write a program to read the length and breadth of a rectangle and find it's area and perimeter.

import java.util.Scanner;

public class j07rectangle {
    public static void main(String[] args) {
        int L,B,A,P;
        Scanner sc= new Scanner(System.in);
        System.out.println("Enter Length:  ");
        L = sc.nextInt();
        System.out.println("Enter Breadth: ");
        B =sc.nextInt();

        A = L*B;
        System.out.println("Area is: "+A);
        P = 2*(L+B);
        System.out.println("Perimeter is: "+P);
    }
}
5.Write a program to exchange the values of two variable using third variable.
import java.util.Scanner;

public class j08exchangevalue {
    public static void main(String[] args) {

        int a,b,temp;
        Scanner sc =new Scanner(System.in);

        System.out.println("Enter Value of a: ");
        a = sc.nextInt();

        System.out.println("Enter Value of b: ");
        b = sc.nextInt();

        //Exchanging Values
        temp = a;
        a = b;
        b = temp;
        System.out.println("a = "+a);
        System.out.println("b = "+b);
    }
}