import sys
input = sys.stdin.readline

class Fenwick_Tree:
    def __init__(self, n):
        self._n = n
        self.data = [0] * n

    def add(self, p, x):
        assert 0 <= p < self._n
        p += 1
        while p <= self._n:
            self.data[p - 1] += x
            p += p & -p

    def sum(self, l, r):
        assert 0 <= l <= r <= self._n
        return self._sum(r) - self._sum(l)

    def _sum(self, r):
        s = 0
        while r > 0:
            s += self.data[r - 1]
            r -= r & -r
        return s

    def get_size(self, x):
        x = self.find(x)
        while r > 0:
            s += self.data[r - 1]
            r -= r & -r
        return s

    def get(self, k):
        k += 1
        x, r = 0, 1
        while r < self._n:
            r <<= 1
        len = r
        while len:
            if x + len - 1 < self._n:
                if self.data[x + len - 1] < k:
                    k -= self.data[x + len - 1]
                    x += len
            len >>= 1
        return x


N, M = map(int, input().split())
mod = 998244353
D = [-1] * N
space = [0] * (N + 1)
num = [1] * N
for i in range(M):
    p, k = map(int, input().split())
    p, k = p - 1, k - 1
    D[k] = p
    num[p] = 0
   
Ac = [0] * (N + 1) 
for i in range(N):
    space[i + 1] = space[i] + (D[i] == -1)    
    Ac[i + 1] = Ac[i] + num[i]
        
nokori = N - M
fact = [1] * (N + 1)
for i in range(N):
    fact[i + 1] = fact[i] * (i + 1)
    fact[i + 1] %= mod
fact.append(0)
    
ans = 0
if nokori >= 2:
    ans += (nokori * (nokori - 1)//2)**2 * fact[nokori - 2]
    ans %= mod
    
T = Fenwick_Tree(N)
for i in range(N):
    if D[i] != -1:
        ans += T.sum(D[i], N) * fact[nokori]
        left = space[i]
        right = nokori - left
        ans += right * Ac[D[i] + 1] * fact[nokori - 1]
        ans += left * (Ac[-1] - Ac[D[i] + 1]) * fact[nokori - 1]
        ans %= mod
        T.add(D[i], 1)
        
print(ans)