//@formatter:off #include #define rep(i,n) for (int i = 0; i < int(n); ++i) #define rrep(i,n) for (int i = int(n)-1; i >= 0; i--) #define rep2(i,s,n) for (int i = int(s); i < int(n); ++i) #define all(a) a.begin(),a.end() #define rall(a) a.rbegin(),a.rend() #define pb push_back #define eb emplace_back #define vi vector #define vvi vector> #define vl vector #define vvl vector> #define vd vector #define vvd vector> #define vs vector #define vc vector #define vvc vector> #define vb vector #define vvb vector> #define vp vector

#define vvp vector> using namespace std; using ll = long long; using P = pair; using LP = pair; template istream& operator>>(istream &is,pair &p) { return is >> p.first >> p.second; } template ostream& operator<<(ostream &os,const pair &p) { return os<<'{'< istream& operator>>(istream &is,vector &v) { for(T &t:v){is>>t;} return is; } template ostream& operator<<(ostream &os,const vector &v) { os<<'[';rep(i,v.size())os< bool chmin(T& a,T b) {if(a > b){a = b; return true;} return false;} template bool chmax(T& a,T b) {if(a < b){a = b; return true;} return false;} const int inf = 1001001001; const ll linf = 1001001001001001001; //@formatter:on //constexpr int mod = 1000000007; constexpr int mod = 998244353; struct mint { ll x; mint(ll x = 0) : x((x % mod + mod) % mod) {} mint operator-() const { return mint(-x); } mint &operator+=(const mint &a) { if ((x += a.x) >= mod) x -= mod; return *this; } mint &operator++() { return *this += mint(1); } mint &operator-=(const mint &a) { if ((x += mod - a.x) >= mod) x -= mod; return *this; } mint &operator--() { return *this -= mint(1); } mint &operator*=(const mint &a) { (x *= a.x) %= mod; return *this; } mint operator+(const mint &a) const { mint res(*this); return res += a; } mint operator-(const mint &a) const { mint res(*this); return res -= a; } mint operator*(const mint &a) const { mint res(*this); return res *= a; } mint pow(ll t) const { mint res = mint(1), a(*this); while (t > 0) { if (t & 1) res *= a; t >>= 1; a *= a; } return res; } // for prime mod mint inv() const { return pow(mod - 2); } mint &operator/=(const mint &a) { return *this *= a.inv(); } mint operator/(const mint &a) const { mint res(*this); return res /= a; } }; ostream &operator<<(ostream &os, const mint &a) { return os << a.x; } void solve() { int n, k; cin >> n >> k; mint ans = mint(2).pow((ll) n * k) - mint(2).pow((ll) (n - 1) * k); ans *= n; cout << ans << endl; } int main() { ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr); int t; cin >> t; rep(i, t) solve(); }