#include <bits/stdc++.h>
#define LL long long
#define lowbit(x) ((x) & (-x))
const int MAXN = 30 + 5;
const int INF = 0x3f3f3f3f;
using namespace std;
 
int main()
{
    //freopen("input.txt", "r", stdin);
    int T, i, j, cases = 0, n;
    while (scanf("%d", &n), n >= 0)
    {
        printf("Case %d: ", ++cases);
        int use = 1, cnt = 0;
        while (1)
        {
            if (n <= use)
                break;
            use <<= 1;
            cnt++;
        }
        printf("%d\n", cnt);
    }
    return 0;
}