#include <cassert>
#include <cmath>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <functional>
#include <iostream>
#include <limits>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

using namespace std;

using Int = long long;

template <class T1, class T2> ostream &operator<<(ostream &os, const pair<T1, T2> &a) { return os << "(" << a.first << ", " << a.second << ")"; };
template <class T> ostream &operator<<(ostream &os, const vector<T> &as) { const int sz = as.size(); os << "["; for (int i = 0; i < sz; ++i) { if (i >= 256) { os << ", ..."; break; } if (i > 0) { os << ", "; } os << as[i]; } return os << "]"; }
template <class T> void pv(T a, T b) { for (T i = a; i != b; ++i) cerr << *i << " "; cerr << endl; }
template <class T> bool chmin(T &t, const T &f) { if (t > f) { t = f; return true; } return false; }
template <class T> bool chmax(T &t, const T &f) { if (t < f) { t = f; return true; } return false; }

////////////////////////////////////////////////////////////////////////////////
template <unsigned M_> struct ModInt {
  static constexpr unsigned M = M_;
  unsigned x;
  constexpr ModInt() : x(0U) {}
  constexpr ModInt(unsigned x_) : x(x_ % M) {}
  constexpr ModInt(unsigned long long x_) : x(x_ % M) {}
  constexpr ModInt(int x_) : x(((x_ %= static_cast<int>(M)) < 0) ? (x_ + static_cast<int>(M)) : x_) {}
  constexpr ModInt(long long x_) : x(((x_ %= static_cast<long long>(M)) < 0) ? (x_ + static_cast<long long>(M)) : x_) {}
  ModInt &operator+=(const ModInt &a) { x = ((x += a.x) >= M) ? (x - M) : x; return *this; }
  ModInt &operator-=(const ModInt &a) { x = ((x -= a.x) >= M) ? (x + M) : x; return *this; }
  ModInt &operator*=(const ModInt &a) { x = (static_cast<unsigned long long>(x) * a.x) % M; return *this; }
  ModInt &operator/=(const ModInt &a) { return (*this *= a.inv()); }
  ModInt pow(long long e) const {
    if (e < 0) return inv().pow(-e);
    ModInt a = *this, b = 1U; for (; e; e >>= 1) { if (e & 1) b *= a; a *= a; } return b;
  }
  ModInt inv() const {
    unsigned a = M, b = x; int y = 0, z = 1;
    for (; b; ) { const unsigned q = a / b; const unsigned c = a - q * b; a = b; b = c; const int w = y - static_cast<int>(q) * z; y = z; z = w; }
    assert(a == 1U); return ModInt(y);
  }
  ModInt operator+() const { return *this; }
  ModInt operator-() const { ModInt a; a.x = x ? (M - x) : 0U; return a; }
  ModInt operator+(const ModInt &a) const { return (ModInt(*this) += a); }
  ModInt operator-(const ModInt &a) const { return (ModInt(*this) -= a); }
  ModInt operator*(const ModInt &a) const { return (ModInt(*this) *= a); }
  ModInt operator/(const ModInt &a) const { return (ModInt(*this) /= a); }
  template <class T> friend ModInt operator+(T a, const ModInt &b) { return (ModInt(a) += b); }
  template <class T> friend ModInt operator-(T a, const ModInt &b) { return (ModInt(a) -= b); }
  template <class T> friend ModInt operator*(T a, const ModInt &b) { return (ModInt(a) *= b); }
  template <class T> friend ModInt operator/(T a, const ModInt &b) { return (ModInt(a) /= b); }
  explicit operator bool() const { return x; }
  bool operator==(const ModInt &a) const { return (x == a.x); }
  bool operator!=(const ModInt &a) const { return (x != a.x); }
  friend std::ostream &operator<<(std::ostream &os, const ModInt &a) { return os << a.x; }
};
////////////////////////////////////////////////////////////////////////////////

constexpr unsigned MO = 998244353;
using Mint = ModInt<MO>;

constexpr int LIM = 500'010;
Mint F[LIM], FSum[LIM + 1];

int N, K;
vector<int> A;

int main() {
  F[1] = 3240;
  F[2] = 3081;
  F[3] = 2841;
  F[4] = 343;
  for (int i = 5; i < LIM; ++i) {
    F[i] = F[i-1] * 223 + F[i-2] * 229 + F[i-3] * F[i-4] * 239 + 17;
  }
  for (int i = 0; i < LIM; ++i) {
    FSum[i + 1] = FSum[i] + F[i];
  }
  
  for (int numCases; ~scanf("%d", &numCases); ) { for (int caseId = 1; caseId <= numCases; ++caseId) {
    scanf("%d%d", &N, &K);
    A.resize(N);
    for (int i = 0; i < N; ++i) {
      scanf("%d", &A[i]);
    }
    
    // 0: to left, 1: to right
    vector<int> weak[2], strict[2];
    for (int h = 0; h < 2; ++h) {
      weak[h].resize(N);
      for (int i = 0; i < N; ++i) {
        int &j = weak[h][i] = i - 1;
        for (; j >= 0 && A[j] < A[i]; j = weak[h][j]) {};
      }
      strict[h].resize(N);
      for (int i = 0; i < N; ++i) {
        int &j = strict[h][i] = i - 1;
        for (; j >= 0 && A[j] <= A[i]; j = strict[h][j]) {}
      }
      reverse(A.begin(), A.end());
    }
    reverse(weak[1].begin(), weak[1].end());
    reverse(strict[1].begin(), strict[1].end());
    for (int i = 0; i < N; ++i) {
      weak[1][i] = N - 1 - weak[1][i];
      strict[1][i] = N - 1 - strict[1][i];
    }
// cerr<<"weak   = "<<weak[0]<<" "<<weak[1]<<endl;
// cerr<<"strict = "<<strict[0]<<" "<<strict[1]<<endl;
    
    Mint ans = 0;
    // x0 < y-p <= x1
    // y0 < y   <= y1
    // z0 < y+p <= z1
    auto add = [&](int x0, int x1, int y0, int y1, int z0, int z1) -> void {
// cerr<<"add "<<x0<<" "<<x1<<" "<<y0<<" "<<y1<<" "<<z0<<" "<<z1<<endl;
      const int lbY = max(y0, (x0 + z0) / 2);
      const int ubY = min(y1, (x1 + z1) / 2);
      for (int y = lbY + 1; y <= ubY; ++y) {
        const int lbP = max(y - x1, z0 - y + 1);
        const int ubP = min(y - x0, z1 - y + 1);
// cerr<<"  "<<y<<" "<<lbP<<" "<<ubP<<endl;
        ans += (A[y - 1] + 10) * (FSum[ubP] - FSum[lbP]);
      }
    };
    // max(left) <= max(right)
    // i: innermost max(left)
    for (int i = 0; i < N; ++i) {
      int j = weak[1][i];
      for (; j < N && A[j] <= A[i] + K; j = strict[1][j]) {}
      add(strict[0][i], i, i, weak[1][i], weak[1][i], j);
    }
    // max(left) > max(right)
    // i: innermost max(right)
    for (int i = 0; i < N; ++i) {
      int j = strict[0][i];
      for (; j >= 0 && A[j] <= A[i] + K; j = strict[0][j]) {}
      add(j, strict[0][i], weak[0][i], i, i, strict[1][i]);
    }
    
    printf("%u\n", ans.x);
  }
#ifndef LOCAL
  break;
#endif
  }
  return 0;
}