Number Transformation

2520 10
2520 20
0 0

Case #1: 2520
Case #2: 2600

//93MS	256K
#include<stdio.h>
#include<string.h>
#define ll __int64
ll a,b;

int main()
{
    int cas=1;
    while(scanf("%I64d%I64d",&a,&b),a|b)
    {
        ll i,c;
        int flag=0;
        for(i=1;i<=b;i++)
        {
            if(a%i)
            {
                c=a/i+1;a=c*i;
                //printf("a=%I64d,c=%I64d,i=%I64d\n",a,c,i);
                if(c<=i){flag=1;break;}
            }
        }
        if(flag)printf("Case #%d: %I64d\n",cas++,c*b);
        else printf("Case #%d: %I64d\n",cas++,a);
    }
}