#pragma GCC target("avx2") #pragma GCC optimize("03") #pragma GCC optimize("unroll-loops") #include using namespace std; typedef long double ld; typedef long long ll; typedef unsigned long long ull; #define endl "\n" #define FOR(i,a,b) for(int i=(a);i<=(b);i++) #define rep(i,n) for(int i=0;i<(n);i++) #define PII pair #define PLL pair #define ALL(x) (x).begin(), (x).end() constexpr int INF=1<<30; constexpr ll LINF=1LL<<60; constexpr ll mod=998244353; constexpr int NIL = -1; templatevector vec(int len, T elem) { return vector(len, elem); } // auto dp = vec(52, vec(103, vec(103, INF))); templateinline bool chmax(T &a, const T &b) { if (ainline bool chmin(T &a, const T &b) { if (binline int popcount(T a) {return __builtin_popcount(a);} templateinline T emod(T a, T p) { return (a%p + p) % p;} template istream &operator>>(istream &is, vector &vec) { for (auto &v : vec) is >> v; return is; } template ostream &operator<<(ostream &os, const vector &vec) {os << '\n'; for (auto v : vec) os << v << ' '; os << '\n'; return os;} template ostream &operator<<(ostream &os, const deque &vec) { os << "deq["; for (auto v : vec) os << v << ','; os << ']'; return os; } template ostream &operator<<(ostream &os, const set &vec) { os << '{'; for (auto v : vec) os << v << ','; os << '}'; return os; } template ostream &operator<<(ostream &os, const unordered_set &vec) { os << '{'; for (auto v : vec) os << v << ','; os << '}'; return os; } template ostream &operator<<(ostream &os, const multiset &vec) { os << '{'; for (auto v : vec) os << v << ','; os << '}'; return os; } template ostream &operator<<(ostream &os, const unordered_multiset &vec) { os << '{'; for (auto v : vec) os << v << ','; os << '}'; return os; } template ostream &operator<<(ostream &os, const pair &pa) { os << '(' << pa.first << ',' << pa.second << ')'; return os; } template ostream &operator<<(ostream &os, const map &mp) { os << '{'; for (auto v : mp) os << v.first << "=>" << v.second << ','; os << '}'; return os; } template ostream &operator<<(ostream &os, const unordered_map &mp) { os << '{'; for (auto v : mp) os << v.first << "=>" << v.second << ','; os << '}'; return os; } //---------------- struct mint { ll x; mint(ll x=0):x(x%mod){} bool operator==(const mint a)const{return x==a.x;} bool operator!=(const mint a)const{return x!=a.x;} bool operator>=(const mint a){return (x >= a.x)? 1: 0;} bool operator<(const mint a){return !(*this>=a);} bool operator>(const mint a){return (x > a.x)? 1:0;} bool operator<=(const mint a){return !(*this>a);} mint& operator+=(const mint a) { if ((x += a.x) >= mod) x -= mod; return *this; } mint& operator-=(const mint a) { if ((x += mod-a.x) >= mod) x -= mod; return *this; } mint& operator*=(const mint a) { (x *= a.x) %= mod; return *this; } mint& operator/=(const mint a) { return (*this) *= a.inv(); } 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 operator/(const mint a) const { mint res(*this); return res/=a; } mint pow(ll t) const { if (!t) return 1; mint a = pow(t>>1); a *= a; //2 square if (t&1) a *= *this; return a; } // for prime mod mint inv() const { return pow(mod-2); } friend ostream& operator<<(ostream& os, const mint& m){ os << m.x; return os; } }; struct combination { vector fact, ifact; combination(int n):fact(n+1),ifact(n+1) { fact[0] = 1; for (int i = 1; i <= n; ++i) fact[i] = fact[i-1]*i; ifact[n] = fact[n].inv(); for (int i = n; i >= 1; --i) ifact[i-1] = ifact[i]*i; } mint operator()(int n, int k) { if (k < 0 || k > n) return 0; return fact[n]*ifact[k]*ifact[n-k]; } } comb(100005); mint f(int n, int k) { if (n < 0) return 0; // nPk = nCk * k! mint res = comb(n,k); res *= comb.fact[k]; return res; } void solve() { int n,k; cin >> n >> k; mint all = mint(2).pow(n).pow(k); mint nt = mint(2).pow(n-1).pow(k); mint ans = (all-nt) * n; cout << ans << endl; } int main() { cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(15); int t; cin >> t; while(t--) solve(); return 0; }