#include <array>
#include <cassert>
#include <cstdint>
#include <iostream>

#include <atcoder/modint>

// <AC>
// 解説通り
int main() {
  using mint = atcoder::modint998244353;
  constexpr int kMaxT = 20000, kMaxN = 10000000;
  constexpr std::int64_t kMaxM = 1000000000000000000;

  using Matrix = std::array<std::array<mint, 2>, 2>;
  const auto Pow = [](const Matrix& x, std::int64_t exponent) -> Matrix {
    const auto Mult = [](const Matrix& x, const Matrix& y) -> Matrix {
      Matrix res{0, 0, 0, 0};
      for (int i = 0; i < 2; ++i) {
        for (int k = 0; k < 2; ++k) {
          for (int j = 0; j < 2; ++j) {
            res[i][j] += x[i][k] * y[k][j];
          }
        }
      }
      return res;
    };
    Matrix res{1, 0, 0, 1}, tmp = x;
    for (; exponent > 0; exponent /= 2) {
      if (exponent % 2 == 1) res = Mult(res, tmp);
      tmp = Mult(tmp, tmp);
    }
    return res;
  };

  // 前計算
  std::array<mint, kMaxN + 1> dp{};
  dp[0] = 1;
  for (int i = 0; i < kMaxN; ++i) {
    dp[i + 1] += dp[i] * (i + 1) * 2;
    if (i + 2 <= kMaxN) dp[i + 2] += dp[i] * (i + 1);
  }

  int t;
  std::cin >> t;
  assert(1 <= t && t <= kMaxT);

  while (t--) {
    int n;
    std::int64_t m;
    std::cin >> n >> m;
    assert(0 <= n && n <= kMaxN && 0 <= m && m <= kMaxM);
    if (n > m) {
      const int tmp = m;
      m = n;
      n = tmp;
    }
    if (n == 0) {
      std::cout << 1 << '\n';
      continue;
    }

    const Matrix matrix = Pow(Matrix{n * 2 + 1, n, 1, 0}, m - n);
    const mint f_m =
        matrix[0][0] * dp[n] + matrix[0][1] * dp[n - 1];  // f(m)
    const mint f_m_1 =
        matrix[1][0] * dp[n] + matrix[1][1] * dp[n - 1];  // f(m - 1)
    const mint ans = f_m * dp[n] + f_m_1 * dp[n - 1] * n;
    std::cout << ans.val() << '\n';
  }
  return 0;
}