There exist a C function to convert an iteger into a char*, but most of the c++ compiler do not support it.
Try this following code to see if it is defined:
#include <stdio.h>
#include <stdlib.h>
using namespace std;
string Text;
itoa( 10, Text, 10 );
If your compilator says that it does not recognize itoa then you will have to write your own function.
Edit:
Or use those proposed by didii