fun main() { val (n, k) = readln().split(" ").map { it.toInt() } if (n == 1) { println(arrayOf(1, 1, 3, 3, 3, 1, 1)[k]) return } var ans = binom(2 * n + 4L, k.toLong()) if (n % 2 == 0 && k % 2 == 0) { ans += ModInt(3) * binom(n + 2L, k / 2L) } else if (n % 2 != 0 && k % 2 == 0) { ans += binom(n + 1L, k / 2L) + binom(n + 1L, (k - 2) / 2L) + ModInt(2) * binom(n + 2L, k / 2L) } else if (n % 2 != 0 && k % 2 != 0) { ans += ModInt(2) * binom(n + 1L, (k - 1) / 2L) } ans /= ModInt(4) println(ans) } // region ModInt class ModInt(x: Long) { companion object { const val MOD = 998244353L } constructor(y: Int) : this(y.toLong()) val x = (x % MOD + MOD) % MOD operator fun plus(other: ModInt): ModInt { return ModInt(x + other.x) } operator fun minus(other: ModInt): ModInt { return ModInt(x - other.x) } operator fun times(other: ModInt): ModInt { return ModInt(x * other.x) } operator fun div(other: ModInt): ModInt { return this * other.inv() } fun pow(exp: Long): ModInt { if (exp == 0L) return ModInt(1L) var a = pow(exp shr 1) a *= a if (exp and 1L == 0L) return a return this * a } fun inv(): ModInt { return this.pow(MOD - 2) } override fun equals(other: Any?): Boolean { if (this === other) return true if (javaClass != other?.javaClass) return false other as ModInt if (x != other.x) return false return true } override fun hashCode(): Int { return x.hashCode() } override fun toString(): String { return "$x" } } fun binom(n: Long, k: Long): ModInt { var numer = ModInt(1) var denom = ModInt(1) for (i in 0 until k) { numer *= ModInt(n - i) denom *= ModInt(k - i) } return numer / denom } // endregion