UVA Solution for 10784

//10784
#include<stdio.h>
#include<math.h>
int main()
{
long n,kase=1,x;
while(scanf("%ld",&n)==1)
{
if(n==0)
break;
//x=ceil(3+sqrt(9+8*n)/2);
x=ceil((3+sqrt(9+8*n))/2);

printf("Case %ld: %ld\n",kase,x);
kase++;
}
}