func main() const mod: int :: 998244353 var t: int :: cui@inputInt() for(1, t) var n: int :: cui@inputInt() var k: int :: cui@inputInt() var ans: @ModInt :: (#@ModInt).init(0, mod) do ans.add(math@modPow(2, n * k, mod)) do ans.sub(math@modPow(2, (n - 1) * k, mod)) do ans.mul(n) do cui@print("\{ans}\n") end for end func ; val, mod, a, b: 0 to 2 ^ 31. class ModInt() +var val: int var mod: int +*func toStr(): []char ret "\{me.val}" end func +func init(val: int, mod: int): ModInt do me.val :: val % mod do me.mod :: mod ret me end func +func add(a: int): ModInt do me.val :+ a if(me.val >= me.mod) do me.val :- me.mod end if ret me end func +func sub(a: int): ModInt if(me.val < a) do me.val :+ me.mod end if do me.val :- a ret me end func +func mul(a: int): ModInt do me.val :: me.val * a % me.mod ret me end func +func div(a: int): ModInt do me.val :: me.val * me.modPow(a, me.mod - 2) % me.mod ret me end func +func pow(a: int): ModInt do me.val :: me.modPow(me.val, a) ret me end func func modPow(a: int, b: int): int if(b = 0) ret 1 end if var res: int :: me.modPow(a, b / 2) do res :: res * res % me.mod if(b % 2 = 1) do res :: res * a % me.mod end if ret res end func end class