#include <bits/stdc++.h>
using namespace std;
const long long maxm = 3e5 + 5;
const long long mod = 998244353;
long long fac[maxm], inv[maxm];
long long l[maxm], r[maxm];
pair<long long, long long> p[25];
long long sum[maxm][45];
long long num[maxm];
long long n, m;
long long ppow(long long a, long long b, long long mod) {
  long long ans = 1 % mod;
  a %= mod;
  while (b) {
    if (b & 1) ans = ans * a % mod;
    a = a * a % mod;
    b >>= 1;
  }
  return ans;
}
void init() {
  fac[0] = 1;
  for (long long i = 1; i < maxm; i++) fac[i] = fac[i - 1] * i % mod;
  inv[maxm - 1] = ppow(fac[maxm - 1], mod - 2, mod);
  for (long long i = maxm - 2; i >= 0; i--) inv[i] = inv[i + 1] * (i + 1) % mod;
}
long long cal(long long x) {
  long long ans = 0;
  while (x) {
    ans++;
    x &= (x - 1);
  }
  return ans;
}
long long C(long long n, long long m) {
  if (m < 0 || m > n) return 0;
  return fac[n] * inv[m] % mod * inv[n - m] % mod;
}
signed main() {
  ios::sync_with_stdio(0);
  init();
  cin >> n >> m;
  for (long long i = 1; i <= n; i++) {
    cin >> l[i] >> r[i];
  }
  for (long long i = 0; i < m; i++) {
    cin >> p[i].first >> p[i].second;
  }
  for (long long i = 1; i <= n; i++) {
    num[l[i]]++;
    num[r[i] + 1]--;
  }
  for (long long i = 1; i <= n; i++) {
    num[i] += num[i - 1];
  }
  for (long long i = 1; i <= n; i++) {
    for (long long j = 0; j <= m * 2; j++) {
      sum[i][j] = (sum[i - 1][j] + C(num[i] - j, i - j)) % mod;
    }
  }
  long long ans = 0;
  for (long long i = 0; i < (1 << m); i++) {
    set<long long> s;
    for (long long j = 0; j < m; j++) {
      if (i >> j & 1) {
        s.insert(p[j].first);
        s.insert(p[j].second);
      }
    }
    long long tot = s.size();
    long long L = 1, R = n;
    for (auto x : s) {
      L = max(L, l[x]);
      R = min(R, r[x]);
    }
    if (L > R) continue;
    long long t = (sum[R][tot] - sum[L - 1][tot] + mod) % mod;
    if (cal(i) & 1) {
      ans = (ans - t + mod) % mod;
    } else {
      ans = (ans + t) % mod;
    }
  }
  cout << ans << endl;
  return 0;
}
