#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef pair<int, int> pii;

const int N = 1e5+10;
const int INF = 2e9;
pii dat[N];

void solve() {
    int n, k;
    scanf("%d%d", &n, &k);
    for (int i = 0; i < n; i++) {
        int x;
        scanf("%d", &x);
        dat[i].first = x - k;
        dat[i].second = x + k;
    }
    sort(dat, dat+n);

    set<int> st;
    int cur = -INF;
    for (int i = 0; i < n; i++) {
        auto p = dat[i];
        cur = max(cur, p.first);
        while (st.count(cur)) cur++;
        if (cur <= p.second) {
            st.insert(cur);
            cur++;
        }
    }

    printf("%d\n", (int)st.size());
}

int main() {
    int T = 1;
    scanf("%d", &T);
    while (T--) solve();
    return 0;
}