FIRST WEEK TERM WORK Program 2

2) Using the concept of abstract class and dynamic method dispatch, write a Java Program that calculates and prints the areas of triangle, square and rectangle. 

package Program2;

abstract class shapes {
abstract void print();

abstract void calc();
}

class triangle extends shapes {
public int a, b, area;

triangle(int p, int q) {
a = p;
b = q;
}

void calc() {

area = a * b;

}

void print() {
System.out.println("Triangle area" + area);
}

}

class rectangle extends shapes {
public int a, b, area;

rectangle(int p, int q) {
a = p;
b = q;
}

void calc() {

area = a * b;

}

void print() {
System.out.println("Rectangle area" + area);
}

}

class square extends shapes {
public int a, area;

square(int p) {
a = p;

}

void calc() {

area = a * a;

}

void print() {
System.out.println("Square area" + area);
}

}

public class ShapesAbstract {
public static void main(String args[]) {
shapes obj = new triangle(5, 10);
obj.calc();
obj.print();
obj = new rectangle(5, 10);
obj.calc();
obj.print();
obj = new square(5);
obj.calc();
obj.print();
}

}