#include <stdio.h>
#include <tuple>
#include <queue>
#include <algorithm>

using namespace std;

typedef tuple <int, int, int> T;

#define range(i,a,b) for(int i=(a); i < (b); i++)
#define rep(i,n) range(i,0,n)

#define UW 5000
#define UH 5000
#define MAXD 25000001

int EX[UH][UW],EY[UW][UH],X[UW+1],Y[UH+1];
int D[UH][UW],dx[]={1,0,-1,0},dy[]={0,1,0,-1};
int main(){
	int W,H,N,M,G,x,y,nx,ny,d;
	queue<T> Q;
	scanf("%d %d %d",&W,&H,&N);
	rep(j,H) rep(i,W){EX[j][i] = EY[i][j] = 0; D[j][i] = MAXD;}
	rep(i,N){
		scanf("%d",&M);
		rep(j,M+1) scanf("%d %d",X+j,Y+j);
		rep(j,M){
			x = X[j];nx = X[j+1];y = Y[j];ny = Y[j+1]; 
			if (y == ny){EX[y][min(x,nx)]++; EX[y][max(x,nx)]--;}
			else {EY[x][min(y,ny)]++; EY[x][max(y,ny)]--;}
		}
	}
	rep(j,H) rep(i,W-1) EX[j][i+1] += EX[j][i];
	rep(i,W) rep(j,H-1) EY[i][j+1] += EY[i][j];

	D[0][0] = 0; Q.push(T(0,0,0)); G = W+H-2;
	while (!Q.empty()){
		tie(x,y,d) = Q.front(); Q.pop();
		if (x+y == G){printf("%d\n",d);return 0;}
		rep(i,4){
			nx = x + dx[i]; ny = y + dy[i];
			if (nx < 0 || nx >= W || ny < 0 || ny >= H) continue;
			if (((x==nx && EY[x][min(y,ny)]>0)||(y==ny && EX[y][min(x,nx)]>0)) && d+1<D[ny][nx]){
				D[ny][nx] = d+1; Q.push(T(nx,ny,d+1));
			}
		}
	}
	puts("Odekakedekinai..");
	return 0;
}