UVA Problem ID :10696(Why I am getting Presentation error?)

[Enayet Kabir]

Here is my source code:
=========================
#include<stdio.h>
long N,result;
long int Mc(long int );
int main()
{

while(scanf("%ld",&N)==1)
{
if(N==0) break;
else
{
result=Mc(N);
printf("f91(%ld) = %ld\n",N,result);
}
}
return 0;
}

long Mc(long int N)
{
if(N>=101)
return (N-10);
else
return (Mc(Mc(N+11)));
}

[brianfry713]

That is AC code.