Question

• Create a menu-based program that will allow the user to calculate the area for a few different shapes: square, rectangle, parallelogram, and circle.
• Refer to the Sample Output in this document to see what menu options you should use.
• Create PI as a global constant variable.
  
• Main Function
  • use do-while to repeat program until user chooses option 5
  • call the displayMenu function
  • get user choice & validate with while loop
  • depending on user’s choice, get the data required to calculate the area of the shape from the user and then call the appropriate function to calculate the area.
    
    
• Write five programmer-defined functions.
  • displayMenu – should print out the menu options
  • areaSquare() – should accept the height of the square from the main function, calculate the area, and then print the area of the square.
  • areaRectangle() – should accept the height & width of the rectangle from the main function, calculate the area, and then print the area of the rectangle.
  • areaParallelogram() – should accept the base & height of the parallelogram from the main function, calculate the area, and then print the area of the parallelogram.

areaCircle() – should accept the radius of the circle from the main function, calculate the area, and then print the area of the circle.

Answer 1

Code:

#include<iostream>
#include<cmath>
using namespace std;
#define PI M_PI
void displayMenu()
{/*printing the menu*/
   cout<<"Menu"<<endl;
   cout<<"1.Area of Square"<<endl;
   cout<<"2.Area of Rectangle"<<endl;
   cout<<"3.Area of Parllelogram"<<endl;
   cout<<"4.Area of Circle"<<endl;
   cout<<"5.Exit"<<endl;
}
double areaSquare(double height)
{/*Returning the area of the square*/
   return(height*height);
}
double areaRectangle(double height,double width)
{/*Returning the area of the rectangle*/
   return(height*width);
}
double areaParllelogram(double base,double height)
{/*Returning the area of the parllelogram*/
   return(base*height);
}
double areaCircle(double radius)
{/*Returning the area of the circle*/
   return(PI*radius*radius);
}
int main()
{
   int choice;
   double height,width,base,radius;/*Declaring variables*/
   do
   {/*This loop iterates untill choice is 5*/
       displayMenu();/*Calling display menu*/
       cout<<"Enter your choice:";
       cin>>choice;/*Reading choice form the user*/
       switch(choice)
       {
           case 1:/*If choice is 1*/
               cout<<"Enter the height of the square:";
               cin>>height;/*Reading height of the square*/
               cout<<"Area of the square is :"<<areaSquare(height)<<endl;
               break;/*Printing the area of square by calling areaSquare function*/
           case 2:/*If choice is 2*/
               cout<<"Enter the height of the rectangle:";
               cin>>height;
               cout<<"Enter the width of the rectangle:";
               cin>>width;/*Reading height and width*/
               cout<<"Area of the Rectangle is :"<<areaRectangle(height,width)<<endl;
               break;/*Printing the result*/
           case 3:/*If choice is 3*/
               cout<<"Enter the base of the parllelogram:";
               cin>>base;
               cout<<"Enter the height of the parllelogram:";
               cin>>height;/*Reading height and base */
               cout<<"Area of the Parllelogram is :"<<areaParllelogram(base,height)<<endl;
               break;/*Printing the result*/
           case 4:/*If choice is 4*/
               cout<<"Enter the radius of the circle:";
               cin>>radius;/*Reading radius form the user*/
               cout<<"Area of the circle:"<<areaCircle(radius)<<endl;
               break;/*printing the result*/
           case 5:/*If choice is 5*/
               break;
           default:
               cout<<"Invalid choice"<<endl;
               break;      
       }  
   }
   while(choice!=5);  
}

Output:

Indentation: