#include <bits/stdc++.h>
using namespace std;
const int MOD = 998244353;
inline void add(int& x, int y) {
  x += y;
  if (x >= MOD) x -= MOD;
}
inline void sub(int& x, int y) {
  x -= y;
  if (x < 0) x += MOD;
}
int pwr(int x, int n) {
  if (!n) return 1;
  if (n % 2) return 1LL * x * pwr(1LL * x * x % MOD, n / 2) % MOD;
  return pwr(1LL * x * x % MOD, n / 2);
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  int n, m;
  cin >> n >> m;
  vector<pair<int, int>> seg(n + 1);
  for (int i = 1; i <= n; i++) cin >> seg[i].first >> seg[i].second;
  vector<pair<int, int>> edg(m);
  for (int i = 0; i < m; i++) cin >> edg[i].first >> edg[i].second;
  vector<vector<int>> evBeg(n + 1), evEnd(n + 2);
  for (int i = 1; i <= n; i++) {
    evBeg[seg[i].first].push_back(i);
    evEnd[seg[i].second + 1].push_back(i);
  }
  vector<int> fact(n + 1);
  fact[0] = 1;
  for (int i = 1; i <= n; i++) fact[i] = 1LL * fact[i - 1] * i % MOD;
  vector<int> mInv(n + 1);
  mInv[n] = pwr(fact[n], MOD - 2);
  for (int i = n - 1; i >= 0; i--) mInv[i] = 1LL * mInv[i + 1] * (i + 1) % MOD;
  auto comb = [&](int n, int k) {
    return 1LL * fact[n] * mInv[k] % MOD * mInv[n - k] % MOD;
  };
  int ans = 0;
  vector<int> lastActEdges(1, -1), math(2 * m + 1);
  int cntActNodes = 0;
  vector<bool> actNodes(n + 1);
  for (int k = 1; k <= n; k++) {
    for (int i : evEnd[k]) {
      cntActNodes--;
      actNodes[i] = false;
    }
    for (int i : evBeg[k]) {
      cntActNodes++;
      actNodes[i] = true;
    }
    if (cntActNodes < k) continue;
    vector<int> actEdges;
    for (int i = 0; i < m; i++)
      if (actNodes[edg[i].first] && actNodes[edg[i].second])
        actEdges.push_back(i);
    int cntActEdges = actEdges.size();
    if (actEdges != lastActEdges) {
      fill(math.begin(), math.end(), 0);
      for (int mask = 0; mask < (1 << cntActEdges); mask++) {
        int bits = 0;
        set<int> nodes;
        for (int bit = 0; bit < cntActEdges; bit++)
          if (mask & (1 << bit)) {
            bits++;
            nodes.insert(edg[actEdges[bit]].first);
            nodes.insert(edg[actEdges[bit]].second);
          }
        math[nodes.size()] += (bits % 2 ? -1 : +1);
      }
      lastActEdges = actEdges;
    }
    for (int i = 0; i <= min(2 * m, k); i++)
      if (math[i] < 0)
        sub(ans, -1LL * math[i] * comb(cntActNodes - i, k - i) % MOD);
      else
        add(ans, +1LL * math[i] * comb(cntActNodes - i, k - i) % MOD);
  }
  cout << ans << '\n';
  return 0;
}
