Thread: Can't compile on the other compiler

A Program runs properly in my compiler and prints the right results, but can't compile in the compiler of a judge. The compiler of the judge says the following:

program.c: In function `int main()':
program.c:25: implicit declaration of function `int ltoa(...)'
--> 25: ltoa( a, string, 10);

I can't understand where the problem is.

The only libraries i use is <stdio.h> and <stdiib.h>.
Is there something wrong with my "ltoa" statement?

i would really appriciate it if you could help me.