import sys
input = sys.stdin.readline
MOD = 998244353

def nPk(n, k):
    ret = 1
    for i in range(n, n - k, -1):
        ret *= i
        ret %= MOD
    return ret


N, M, K = map(int, input().split())
edges = [[x - 1 for x in map(int, input().split())] for _ in [0] * K]

toposo_st = set([])
for edge in edges:
    toposo_st |= set(edge)
toposo_ids = { x : i for i, x in enumerate(toposo_st)}
t = len(toposo_st)

graph = [[0] * t for _ in [0] * t]
for x, y in edges:
    graph[toposo_ids[x]][toposo_ids[y]] = 1

def can_set_left(s, i):
    for j in range(t):
        if(i == j or not((s >> j) & 1)):
            continue
        if(graph[j][i] == 0):
            continue
        return False
    return True

dp = [-1] * (1 << t)
dp[0] = 1
def count_toposo(s):
    global dp
    if(dp[s] == -1):
        dp[s] = 0
        for i in range(t):
            if not((s >> i) & 1):
                continue
            if(can_set_left(s, i)):
                dp[s] += count_toposo(s - (1 << i))
        dp[s] %= MOD
    return dp[s]

ans = 0
p1 = nPk(N - 1, N - t)
p2 = nPk(N - 1, N - t - 1)
for i in range(M, N):
    if(i in toposo_st):
        id = toposo_ids[i]
        if not(can_set_left((1 << t) - 1, id)):
            continue
        ans += p1 * count_toposo((1 << t) - 1 - (1 << id)) % MOD
    else:
        ans += p2 * count_toposo((1 << t) - 1) % MOD
ans %= MOD
print(ans)