Please help

I m new to Codechef....but i m not able to get even one successful submition.....my code is working fine ,in IDE i m using..but here it shows some or the other error..... even for the question (section:PRACTICE/EASY last question) :Life, the Universe, and Everything why this code is not working..?c++(gcc-4.3.2)

#include<iostream>
using namespace std;
int main()
{
int num;
do
{
cin>>num;
if(num==42)
break;
else
cout<<num;
}while(1);
return 0;
}