#include <cstdio>
#include <cstring>
#include <iostream>
#include <string>
#include <cmath>
#include <bitset>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <algorithm>
#include <complex>
#include <unordered_map>
#include <unordered_set>
#include <random>
#include <cassert>
#include <fstream>
#include <utility>
#include <functional>
#include <time.h>
#include <stack>
#include <array>
#include <list>
#include <atcoder/all>
#define popcount __builtin_popcount
using namespace std;
using namespace atcoder;
typedef long long ll;
typedef pair<ll, int> P;
using mint=modint998244353;
mint f[2000010], invf[2000010];
void fac(int n){
    f[0]=1;
    for(ll i=1; i<=n; i++) f[i]=f[i-1]*i;
    invf[n]=f[n].inv();
    for(ll i=n-1; i>=0; i--) invf[i]=invf[i+1]*(i+1);
}
mint comb(int x, int y){
    if(!(0<=y && y<=x)) return 0;
    return f[x]*invf[y]*invf[x-y];
}
vector<P> g[300030];
ll d[300030];
int main()
{
    int n, m;
    cin>>n>>m;
    
    for(int i=0; i<m; i++){
        int k; cin>>k;
        int c; cin>>c;
        for(int j=0; j<k; j++){
            int s; cin>>s;s--;
            if(s&1){
                g[s].push_back({n+i, s+c+1});
                g[n+i].push_back({s, s+c+1});
            }else{
                g[s].push_back({n+i+m, s+c+1});
                g[n+i+m].push_back({s, s+c+1});
            }
        }
        g[n+i+m].push_back({n+i, 1});
        g[n+i].push_back({n+i+m, 1});
    }
    const ll INF=1e18;
    
    fill(d, d+n+2*m, INF);
    d[0]=0;
    priority_queue<P, vector<P>, greater<P>> que;
    que.push({0, 0});
    while(!que.empty()){
        auto p=que.top();que.pop();
        int x=p.second;
        if(d[x]<p.first) continue;
        for(auto q:g[x]){
            int y=q.first;
            if(d[y]>d[x]+q.second){
                d[y]=d[x]+q.second;
                que.push({d[y], y});
            }
        }
    }
    if(d[n-1]<INF/2) cout<<d[n-1]/2<<endl;
    else cout<<-1<<endl;
    return 0;
}