divisible by 3

#include<stdio.h>
int main()
{
    long long unsigned t,j,i,w,m,n,s,c,count;
    scanf("%llu",&t);
    for(i=0; i<t; i++)
    {
        count=0;
        scanf("%llu %llu",&m,&n);
        if(m==n)
        {
            count=1;
            printf("Case %llu: %llu\n",i+1,count);
            continue;
        }


        m=(2*m)/3;
        n=(2*n)/3;
        count=n-m;
        printf("Case %llu: %llu\n",i+1,count);
    }
}