URLs in C

Here is a C puzzle I like to ask my friends and colleagues. It is one of those silly puzzles that may bring a smile on your face if you aren't able to figure it out immediately.

#include <stdio.h>

int main()
{
http://susam.in/
printf("hello, world\n");
return 0;
}


This code compiles and runs successfully even though the current draft of the C99 standard doesn't mention anywhere that URLs are valid syntactic elements in C. How does this code work then?

9 comments

kunkunur said:

is it like this?

http: is considered as label and the rest is considered as comment?

Mandeep said:

http: makes it a label...and the rest is a comment! :P

nice one.

abhay said:

smart hack. both kunkunar and Mandeep are correct.

Iouri said:

url.c: In function ‘main’: url.c:5: warning: label ‘http’ defined but not used

Yuvi Panda said:

Nice one! And yay, I got it under a 10 seconds too :D :D

Anuvrat said:

comment was obvious but labels were not. awesome!!!

krace-the kingmaker said:

Nice question ,checks depth of understanding in C.

Vikas Burte said:

Simple yet cryptic! Basics!

good one