Program to find parameter and area of circle according to choice in c language.

#include<stdio.h>

#include<conio.h>

void main()

{

    int choice;

    float r,area,per;

    clrscr();

    printf("press 1 for area.\n");

    printf("press 2 for parameter.\n");

    printf("enter the radius of circle=");

    scanf("%f",&r);

    printf("\nenter your choice=");

    scanf("%d",&choice);

    switch(choice)

    {

    case 1:

              area=3.14*r*r;

              printf("the area of circle is =%f",area);

              break;

    case 2:

              per=2*3.14*r;

              printf("the parameter of circle is=%f",per);       

              break;    

    default:

              printf("wrong choice.");         

    }

    getch();

}

■》 Output->

Press 1 for area.

press 2 for parameter.

enter the radius of circle=10

enter your choice=2

 

the parameter of circle is=62.799999