import sys
readline = sys.stdin.readline
w,h,n = map(int,input().split())

b1 = [[0]*w for _ in range(h)]
b2 = [[0]*h for _ in range(w)]

for _ in range(n):
    m = int(readline())
    t = list(map(int,input().split()))
    for i in range(m):
        x,y = t[i],t[i+1]
        if x > y: x,y = y,x
        if y-x < w:
            b1[x//w][x%w] += 1
            b1[y//w][y%w] -= 1
        else:
            b2[x%w][x//w] += 1
            b2[y%w][y//w] -= 1

for i in range(h):
    for j in range(1,w):
        b1[i][j] += b1[i][j-1]
for j in range(w):
    for i in range(1,h):
        b2[j][i] += b2[j][i-1]

from collections import deque
q = deque([(0,0)])
b = [[-1]*w for _ in range(h)]
b[0][0] = 0
while q:
    vi,vj = q.popleft()
    d = b[vi][vj]
    if vj and b1[vi][vj-1] and b[vi][vj-1]==-1:
        b[vi][vj-1] = d+1
        q.append((vi,vj-1))
    if vj+1<w and b1[vi][vj] and b[vi][vj+1]==-1:
        b[vi][vj+1] = d+1
        q.append((vi,vj+1))
    if vi and b2[vj][vi-1] and b[vi-1][vj]==-1:
        b[vi-1][vj] = d+1
        q.append((vi-1,vj))
    if vi+1<h and b2[vj][vi] and b[vi+1][vj]==-1:
        b[vi+1][vj] = d+1
        q.append((vi+1,vj))
print(b[h-1][w-1] if b[h-1][w-1] != -1 else "Odekakedekinai..")