#include <bits/stdc++.h>
#define For(i,l,r) for (register int i=l; i<=r; i++)
using namespace std;
typedef unsigned long long LL;
typedef signed long long ll;
template <typename T>
inline void read(T &x) {
    char c = getchar(); int w = 1; x = 0;
    while (!isdigit(c))
        (c == '-') && (w = -w), c = getchar();
    while (isdigit(c))
        x = (x << 1) + (x << 3) + (c ^ '0'), c = getchar();
    x *= w;
}

const int N = 100010;
ll T, n, k, a[N], ans = 0;
signed main() {
    read(T);
    while (T -- > 0) {
        read(n); read(k);
        for (register int i=1; i<=n; ++i) {
            read(a[i]);
        }
        std :: sort(a + 1, a + n + 1);
        ll last = -1000000000;
        ans = 0;
        for (register int i=1; i<=n; ++i) {
            if (a[i]-k > last) {
                ans += k * 2 + 1; last = a[i] + k;
            }
            else {
                ans += a[i]+k-last; last = a[i] + k;
            }
        }
        printf("%lld\n", min(ans, n));
    }
    getchar();
    return 0;
}