#include "bits/stdc++.h"
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> veci;
typedef vector<string> vecs;
template<class T,class U> using Hash=unordered_map<T,U>;

#define REP(i, a, n) for(ll i = a; i < n; i++)
#define rep(i, n) REP(i, 0, n)

template<class T> T read(){T a;cin >> a;return a;}
template<class T> T read(T& a){cin >> a;}
template<class T> void rarr(T a, int n){for(int i = 0; i < n; i++) {cin >> a[i];}}
template<class T> void write(T a){cout << a << endl;}
void write(double a){cout << fixed << setprecision(12) << a << endl;}
template<class T> void warr(T a, int n, char* c = " "){cout << a[0];for(int i = 1; i < n; i++)cout << c << a[i];cout << endl;}
ll gcd(ll a, ll b){while(true){ll k = a % b;if(k == 0)return b;a = b;b = k;}}

int main(void)
{
    int w,h,n;
    Hash<int,bool>* a=new Hash<int,bool>[1000*1000];
    cin>>w>>h>>n;
    rep(i,n) {
        int m=read<int>();
        int bf=read<int>();
        rep(j,m){
            int b=read<int>();
            int sign=(b<bf)?1:-1;
            int sb=b;
            if(b%w==bf%w)
                while(sb!=bf){
                    a[sb][sb+w*sign]=a[sb+w*sign][sb]=true;
                    sb+=w*sign;
                }
            else
                while(sb!=bf){
                    a[sb][sb+sign]=a[sb+sign][sb]=true;
                    sb+=sign;
                }
            bf=b;
        }
    }
    bool vis[1000*1000]={0};
    queue<int> q;
    int res[1000*1000]={0};
    int WH=w*h-1;
    q.push(0);
    vis[0]=true;
    while(!q.empty()){
        int cur=q.front();
        q.pop();
        for(auto p : a[cur]){
            if(!vis[p.first]){
                vis[p.first]=true;
                res[p.first]=res[cur]+1;
                q.push(p.first);
            }
        }
        if(vis[WH])
            break;
    }
    if(vis[WH])
        write(res[WH]);
    else
        write("Odekakedekinai..");
	return 0;
}