MOD = 998244353

h, w = map(int, input().split())
assert 3 <= h <= 1000
assert 3 <= w <= 1000

U = list(map(int, input().split()))
L = [0] * h
R = [0] * h
L[0] = U[0]
R[0] = U[-1]
for i in range(1, h - 1):
    L[i], R[i] = map(int, input().split())
D = list(map(int, input().split()))
L[-1] = D[0]
R[-1] = D[-1]

for i in range(h - 1):
    if abs(L[i] - L[i + 1]) > 1:
        print(-1)
        exit()

    if abs(R[i] - R[i + 1]) > 1:
        print(-1)
        exit()

for i in range(w - 1):
    if abs(U[i] - U[i + 1]) > 1:
        print(-1)
        exit()

    if abs(D[i] - D[i + 1]) > 1:
        print(-1)
        exit()

row = False
for i in range(h):
    d = abs(L[i] - R[i])
    if d > w - 1:
        row = True

col = False
for i in range(w):
    d = abs(U[i] - D[i])
    if d > h - 1:
        col = True

assert not row or not col
if not row and not col:
    print(1)
    exit()

if col:
    L, R, U, D = U, D, L, R
    h, w = w, h

dp = [0] * (w - 1)
dp[-1] = 1

for i in range(1, h - 1):
    ndp = [0] * (w - 1)
    d = abs(L[i] - R[i])
    if d <= w - 1:
        ndp[-1] = sum(dp) % MOD
        dp = ndp
        continue

    uu = abs(L[i] - R[i - 1]) > w
    dd = abs(L[i - 1] - R[i]) > w
    if uu and dd:
        for j in range(w - 2):
            ndp[j] += dp[-1]
            if j != 0:
                ndp[j] += dp[j - 1]
            ndp[j] += dp[j]
            if j != w - 3:
                ndp[j] += dp[j + 1]
            ndp[j] %= MOD
    elif uu:
        for j in range(1, w - 2):
            dp[j] += dp[j - 1]
            dp[j] %= MOD
        for j in range(w - 2):
            ndp[j] += dp[-1]
            if j != w - 3:
                ndp[j] += dp[j + 1]
            else:
                ndp[j] += dp[j]
            ndp[j] %= MOD
    elif dd:
        for j in range(w - 4, -1, -1):
            dp[j] += dp[j + 1]
            dp[j] %= MOD
        for j in range(w - 2):
            ndp[j] += dp[-1]
            if j != 0:
                ndp[j] += dp[j - 1]
            else:
                ndp[j] += dp[j]
            ndp[j] %= MOD
    else:
        tot = sum(dp) % MOD
        ndp = [tot] * (w - 1)
        ndp[-1] = 0

    dp = ndp

ans = sum(dp) % MOD
print(ans)