#include using namespace std; template struct ModInt{ long long val; static constexpr int mod() { return Modulus; } constexpr ModInt(const long long _val = 0) noexcept : val(_val) { normalize(); } void normalize(){ val = (val % Modulus + Modulus) % Modulus; } inline ModInt &operator+=(const ModInt &rhs) noexcept { if(val += rhs.val, val >= Modulus) val -= Modulus; return *this; } inline ModInt &operator-=(const ModInt &rhs) noexcept { if(val -= rhs.val, val < 0) val += Modulus; return *this; } inline ModInt &operator*=(const ModInt &rhs) noexcept { val = val * rhs.val % Modulus; return *this; } inline ModInt &operator/=(const ModInt &rhs) noexcept { val = val * inv(rhs.val).val % Modulus; return *this; } inline ModInt &operator++() noexcept { if(++val >= Modulus) val -= Modulus; return *this; } inline ModInt operator++(int) noexcept { ModInt t = val; if(++val >= Modulus) val -= Modulus; return t; } inline ModInt &operator--() noexcept { if(--val < 0) val += Modulus; return *this; } inline ModInt operator--(int) noexcept { ModInt t = val; if(--val < 0) val += Modulus; return t; } inline ModInt operator-() const noexcept { return (Modulus - val) % Modulus; } inline ModInt inv(void) const { return inv(val); } ModInt pow(long long n) const { assert(0 <= n); ModInt x = *this, r = 1; while(n){ if(n & 1) r *= x; x *= x; n >>= 1; } return r; } ModInt inv(const long long n) const { long long a = n, b = Modulus, u = 1, v = 0; while(b){ long long t = a / b; a -= t * b; std::swap(a, b); u -= t * v; std::swap(u, v); } u %= Modulus; if(u < 0) u += Modulus; return u; } friend inline ModInt operator+(const ModInt &lhs, const ModInt &rhs) noexcept { return ModInt(lhs) += rhs; } friend inline ModInt operator-(const ModInt &lhs, const ModInt &rhs) noexcept { return ModInt(lhs) -= rhs; } friend inline ModInt operator*(const ModInt &lhs, const ModInt &rhs) noexcept { return ModInt(lhs) *= rhs; } friend inline ModInt operator/(const ModInt &lhs, const ModInt &rhs) noexcept { return ModInt(lhs) /= rhs; } friend inline bool operator==(const ModInt &lhs, const ModInt &rhs) noexcept { return lhs.val == rhs.val; } friend inline bool operator!=(const ModInt &lhs, const ModInt &rhs) noexcept { return lhs.val != rhs.val; } friend inline std::istream &operator>>(std::istream &is, ModInt &x) noexcept { is >> x.val; x.normalize(); return is; } friend inline std::ostream &operator<<(std::ostream &os, const ModInt &x) noexcept { return os << x.val; } }; template T intpow(T x, int n){ T ret = 1; while(n > 0) { if(n & 1) (ret *= x); (x *= x); n >>= 1; } return ret; } const long long MOD = 998244353; using mint = ModInt; int main(){ int t; cin >> t; while(t--){ long long n; int k; cin >> n >> k; long long p = intpow(10LL, k); long long a = n / p, b = n % p; mint ans = 0; auto choose2 = [](long long x) -> mint { return mint(x) * (x - 1) / 2; }; // 上の桁が N と同じ { mint c = choose2((p + 1) / 2) + choose2(p / 2); c -= choose2((p - b + 1) / 2) + choose2((p - b) / 2); c *= a / 2; ans += c; } // それ以外 { mint c = choose2((p + 1) / 2) + choose2(p / 2); c *= choose2((a + 1) / 2) + choose2(a / 2); ans += c; } cout << ans << endl; } }