/***********************************************
** Remy's Circle Equation Calculation Program **
************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
#include <ctype.h>

#define PI 3.14

float a, c, r, x;
char quit;

float area(void);
float circ(void);

int main()
{
	do {
		printf("Press A for area, C for circumference.\n");
		c=toupper(getch());
		
		if (c=='A')
		{
			printf("You chose area.\n");
			printf("Enter the radius:");	
   
			a=area();
			printf("The area of the circle is %f.\n",a);
	
			printf("Do you want to quit? Y/\N?\n");
			quit=toupper(getch());
		}
	
		else if (c=='C')
		{
			printf("You chose circumference.\n");
			printf("Enter the radius:");
	
			c=circ();
			printf("The circumference of the circle is %f.\n",c);
		
			printf("Do you want to quit? Y/\N?\n");
			quit=toupper(getch());
		}

		else
		{
			printf("Invalid choice.\n");
		
			printf("Do you want to quit? Y/\N?\n");
			quit=toupper(getch());
		}
	}

	while (quit == 'N');
		return 0;
}

float area(void)
{
	scanf("%f", &r);
	x=PI*(r*r);

	return(x);
}	

float circ(void)
{
	scanf("%f", &r);
	x=2*PI*r;

	return(x);
}