#include <bits/stdc++.h>
using i64 = long long;
using namespace std;
const int N = 1e6 + 5;
// const int B = 340;
// const int M = 5e3 + 5;
// const int base = 1753591;
// const int mod = 998244353;
const int mod = 1e9 + 7;
// const double pi = acos(-1);

int n, a[N];
i64 k;
void solve()
{
    cin >> n >> k;
    for (int i = 1; i <= n; i++)
        cin >> a[i];
    for (int i = n; i >= 2; i--)
        a[i] -= a[i - 1];
    int ans = 1;
    i64 sum = 0;
    for (int i = 2, pre = 2; i <= n; i++)
    {
        sum += abs(a[i] - 1);
        while (sum > k)
        {
            sum -= abs(a[pre] - 1);
            pre++;
        }
        ans = max(ans, i - pre + 2);
    }
    cout << ans << '\n';
}
signed main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int t = 1;
    cin >> t;
    cout << fixed << setprecision(10);
    while (t--)
        solve();
}