#include <cassert>
#include <cmath>
#include <algorithm>
#include <iostream>
#include <iomanip>
#include <climits>
#include <map>
#include <queue>
#include <set>
#include <cstring>
#include <vector>

using namespace std;
typedef long long ll;

const ll MOD = 998244353;

ll mod_pow(ll x, ll n, ll mod = MOD) {
  ll res = 1;

  while (n > 0) {
    if (n & 1) {
      res = res * x % mod;
    }

    x = x * x % mod;
    n >>= 1;
  }

  return res;
}

struct Node {
  int l;
  int r;

  Node(int l = -1, int r = -1) {
    this->l = l;
    this->r = r;
  }

  bool operator>(const Node &n) const {
    return l > n.l;
  }
};

struct Node2 {
  int l;
  int r;

  Node2(int l = -1, int r = -1) {
    this->l = l;
    this->r = r;
  }

  bool operator>(const Node2 &n) const {
    return r > n.r;
  }
};

int main() {
  ll N, K;
  cin >> N >> K;
  int L[N];
  int R[N];

  priority_queue <Node, vector<Node>, greater<Node>> pque_1;

  for (int i = 0; i < N; ++i) {
    cin >> L[i] >> R[i];

    pque_1.push(Node(L[i], R[i]));
  }

  ll all = mod_pow(K, N);
  ll cnt = 1;
  priority_queue <Node2, vector<Node2>, greater<Node2>> pque_2;

  while (not pque_1.empty()) {
    Node node = pque_1.top();
    pque_1.pop();

    while (not pque_2.empty() && pque_2.top().r <= node.l) {
      pque_2.pop();
    }

    ll m = pque_2.size();
    cnt *= (K - m);
    cnt %= MOD;

    pque_2.push(Node2(node.l, node.r));
  }

  cout << (all - cnt + MOD) % MOD << endl;

  return 0;
}