No Output No Error what's wrong in the code

[mkbutan]

Its a Question in the book of
PROGRAMMING IN ANIC C
the question is :-

Given the radius of a circle, write a program to compute and display its area.
Use a symbolic constane to define the ∏(pi) value and assume a suitable value for radius.

my Answer

/*  
Name: mkbutan  
Copyright:   
Author:   
Date: 03/08/12 13:50  
Description: exec 1.5 pg 21 New
*/
#include<stdio.h>
#include<conio.h>
void main()
{
     int r,x;     
float pi;     
/*printf("Enter the Radius : \n",r);     
scanf("%d",r);*/     
pi = (22/7);     
r = 5;    
 x = (pi*r*r);     
printf("The Area of a Circle is : %d",x);     
getch();     
}

but i dont get any output and there is no error


pl help

[grumpy]

Some modern compilers reject void main(), so will refuse to compile your code. Main actually returns int. Also, a fair few compilers also do not recognise <conio.h> and the getch() function, so will refuse to compile your code.

If the compiler does not successfully compile your code, it cannot be run, so cannot produce output.

If you are attempting to run your program from an IDE, you need to pay attention. Just telling the IDE to run does not magically repair faulty code and execute your program. When compilers emit error messages, they are usually displayed in some window or part of the screen managed by the IDE. Your not looking at the error messages does not change that fact.

Also, the value 22/7 is computed using integer arithmetic, so your value of pi will have the value of 3. Even if the calculation was done as floating point, 22/7 is still a poor approximation of pi (it is only accurate to within two decimal places).

[whiteflags]

My personal favorite approximation of pi is 355/113.0 ... quite easy for the precision you get.

[Adak]

What happened to the "define a symbolic constant"?

Maybe you want #define PI 3.14159 or const double Pi = 3.14159

The assignment is short, but you're taking it too lightly. Perhaps take a break and get back to it when you're fresher.

[dmh2000]

on linux, if you don't have a '\n' as the last output in your printf, the buffer doesn't get flushed imediately and you don't see anything until it sees a \n, fflush(stdout) or the program terminates. but your output would be shown after you hit a character and passed the getc.