fun main() { val (n, k) = nextInts() val customers = mutableListOf>() for (i in 0 until n) { val (l, r) = nextInts() customers.add(l to r) } customers.sortBy { it.first } val bit = BIT(200005) var compl = ModInt(1) for ((l, r) in customers) { compl *= ModInt(k - bit.sum(l + 1 until 200005)) bit.add(r, 1) } val ans = ModInt(k).pow(n.toLong()) - compl println(ans) } class BIT(private val n: Int) { private val data = LongArray(n) { 0 } fun add(i: Int, x: Long) { var p = i + 1 while (p <= n) { data[p - 1] += x p += p and -p } } fun sum(range: IntRange): Long { val l = range.first val r = range.last + 1 return sum(r) - sum(l) } private fun sum(i: Int): Long { var r = i var s = 0L while(r > 0) { s += data[r - 1] r -= r and -r } return s } } // region ModInt class ModInt(x: Long) { companion object { //const val MOD = 1000000007L 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 Long.toModInt(): ModInt { return ModInt(this) } fun Int.toModInt(): ModInt { return ModInt(this) } fun binomSimple(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 fun nextInts() = readln().split(" ").map { it.toInt() }