#include <cstdio>
#include <map>
using namespace std;

const int Maxn = 100005;

int t;
int n, a;
int s[Maxn];
map <int, int> M;
int res;

bool Ok()
{
    if (M.empty()) return true;
    map <int, int>::iterator st = M.begin(), en = M.end(); en--;
    return en->first - st->first <= a;
}

int main()
{
    scanf("%d", &t);
    for (int tc = 1; tc <= t; tc++) {
        scanf("%d %d", &n, &a);
        for (int i = 0; i < n; i++)
            scanf("%d", &s[i]);
        res = 0;
        int r = 0;
        for (int l = 0; l < n; l++) {
            while (r < n && Ok()) { M[s[r]]++; r++; }
            int got = r - l - bool(!Ok());
            res = max(res, got);
            if (--M[s[l]] == 0) M.erase(s[l]);
        }
        printf("Case #%d: %d\n", tc, res);
    }
    return 0;
}