from sys import stdin
from Queue import deque
dx = (1,0,-1,0); dy = (0,1,0,-1); di = range(4)
W,H,N = map(int,stdin.readline().split())
RH = [None]*H; MD = W*H+1
EX = [[0]*W for j in RH]
EY = [[0]*H for i in [None]*W]
for i in [None]*N:
    M = int(stdin.readline())
    x,y = map(int,stdin.readline().split())
    for j in [None]*M:
        nx,ny = map(int,stdin.readline().split())
        if y == ny:
            if x < nx: EX[y][x]+=1; EX[y][nx]-=1
            else: EX[y][nx]+=1; EX[y][x]-=1
        else: 
            if y < ny: EY[x][y]+=1; EY[x][ny]-=1
            else: EY[x][ny]+=1; EY[x][y]-=1
        x,y = nx,ny
for j in xrange(H):
    for i in xrange(W-1):EX[j][i+1] += EX[j][i]
for i in xrange(W):
    for j in xrange(H-1):EY[i][j+1] += EY[i][j]
D = [[MD]*W for i in RH]
D[0][0] = 0; G = W+H-2
Q = deque([(0,0,0)])
while Q:
    x,y,d = Q.popleft()
    if x+y == G:
        print d; break
    for i in di:
        if dx[i] > 0:
            nx = x + 1
            if nx < W and EX[y][x]>0 and D[y][nx] > d+1:
                D[y][nx] = d+1; Q.append((nx,y,d+1))
        elif dx[i] < 0:
            nx = x - 1
            if nx >= 0 and EX[y][nx]>0 and D[y][nx] > d+1:
                D[y][nx] = d+1; Q.append((nx,y,d+1))
        elif dy[i] > 0:
            ny = y + 1
            if ny < H and EY[x][y]>0 and D[ny][x] > d+1:
                D[ny][x] = d+1; Q.append((x,ny,d+1))
        else:
            ny = y - 1
            if ny >= 0 and EY[x][ny]>0 and D[ny][x] > d+1:
                D[ny][x] = d+1; Q.append((x,ny,d+1))
else:
    print "Odekakedekinai.."