func main() var n: int :: cui@inputInt() var k: int :: cui@inputInt() var a: []int :: #[n]int var sum: int :: 0 for i(0, n - 1) do a[i] :: cui@inputInt() do sum :+ a[i] end for var ans: modInt :: (#modInt).init(2, 998244353) do ans.pow(k) do ans.mul(sum) do cui@print("\{ans}\n") class modInt() +var val: int var mod: int +func init(val: int, mod: int): modInt do me.val :: val do me.mod :: mod ret me end func +func add(a: int): modInt do me.val :: (me.val + a) % me.mod ret me end func +func sub(a: int): modInt do me.val :: (me.val + me.mod - a) % me.mod ret me end func +func mul(a: int): modInt do me.val :: math@modMul(me.val, a, me.mod) ret me end func +func div(a: int): modInt do me.val :: me.val * math@modPow(a, me.mod - 2, me.mod) % me.mod ret me end func +func pow(a: int): modInt do me.val :: math@modPow(me.val, a, me.mod) ret me end func +*func toStr(): []char ret "\{me.val}" end func end class end func