UVA 12004

    #include <cstdio>
     
    using namespace std;
     
    int main(){
        int T,n;
     
        scanf("%d",&T);
     
        for(int tc = 1;tc <= T;++tc){
            scanf("%d",&n);
     
            long long ans = (long long)n * (n-1);
     
            printf("Case %d: ",tc);
     
            if(ans % 4 == 0) printf("%lld\n",ans / 4);
            else printf("%lld/2\n",ans / 2);
        }
     
        return 0;
    }