#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define pli pair <ll,int> 
const int N = 2e5;
int n,m,k,u,v,w,p,a[N + 5],cnt;
int id[2 * N + 5],fail[2 * N + 5];
int vis[2 * N + 5];
ll dis[2 * N + 5],ans; 
struct edge
{
	int v,w;
	bool operator < (const edge &y)const
	{
		return v < y.v;
	}
};
vector <edge> e[N + 5],now;
set <pair <int,int> > s;
map <int,int> mp[2 * N + 5];
queue <int> q;
struct Segment_Tree
{
	#define ls a[id].l
	#define rs a[id].r
	struct node
	{
		int l,r,val,id;
	}a[60 * N + 5];
	int cntnode;
	int update(int id,int l,int r,int x,int v,int w) 
	{
		a[++cntnode] = a[id];id = cntnode;
		if(l == r)
		{
			if(w != -1)a[id].val = w; 
			return a[id].id = v,id;
		}
		int mid = l + r >> 1;
		if(x <= mid)ls = update(ls,l,mid,x,v,w);
		else rs = update(rs,mid + 1,r,x,v,w);
		return id;
	}
	int query(int id,int l,int r,int x)
	{
		if(l == r)return a[id].id;
		int mid = l + r >> 1;
		if(x <= mid)return query(ls,l,mid,x);
		return query(rs,mid + 1,r,x);
	}
	int get(int id,int l,int r,int u,vector <edge> &ne)
	{
		if(!id)return 0;
		if(l == r)return ne.push_back({a[id].id,a[id].val}),0;
		int mid = l + r >> 1;
		ls = get(ls,l,mid,u,ne);
		rs = get(rs,mid + 1,r,u,ne);
		return 0;
	}
}st;
int rt[2 * N + 5];
void dij(int s)
{
	priority_queue <pli,vector <pli>,greater <pli> > q; 
	memset(dis,0x3f,sizeof(dis));
	dis[s] = 0;q.push({dis[s],s});
	while(!q.empty())
	{
		int u = q.top().second;q.pop();
		if(vis[u])continue;vis[u] = 1;
		now.clear();
		rt[u] = st.get(rt[u],1,n,u,now);
		for(auto v : now)
			if(!vis[v.v]&&dis[u] + v.w < dis[v.v])
				dis[v.v] = dis[u] + v.w,
				q.push({dis[v.v],v.v});
	}
}
int main()
{
	freopen("compete.in","r",stdin);
	freopen("compete.out","w",stdout);
	scanf("%d %d %d",&n,&m,&k);
	for(int i = 1;i <= m;i++)
		scanf("%d %d %d",&u,&v,&w),
		e[u].push_back({v,w}),
		s.insert({u,v});
	int Rt = n + 1;
	for(int i = 1;i <= n;i++)mp[Rt][i] = i,id[i] = i;
	cnt = Rt;
	while(k--)
	{
		scanf("%d",&p);
		for(int i = 1;i <= p;i++)scanf("%d",&a[i]);
		int f = 1;
		for(int i = 2;i <= p;i++)
			if(s.find({a[i - 1],a[i]}) == s.end())
				f = 0;
		if(!f)continue;
		int now = n + 1;
		for(int i = 1;i <= p;i++)
		{
			if(mp[now].find(a[i]) == mp[now].end())
				mp[now][a[i]] = ++cnt,id[cnt] = a[i];
			now = mp[now][a[i]];
		}
		vis[now] = 2;
	}
	for(int i = 1;i <= n;i++)
	{
		for(auto v : e[i])
			rt[i] = st.update(rt[i],1,n,v.v,v.v,v.w);
		fail[i] = Rt,q.push(i);
	}
	while(!q.empty())
	{
		int u = q.front();q.pop();
		if(u > n)rt[u] = rt[fail[u]];
		vis[u] |= vis[fail[u]];
		for(auto now : mp[u])
		{
			int v = now.first,nxt = now.second;
			rt[u] = st.update(rt[u],1,n,v,nxt,-1);
			if(u <= n)fail[nxt] = v;
			else fail[nxt] = st.query(rt[fail[u]],1,n,v);
			q.push(nxt);vis[nxt] |= vis[u];
		}
	}
	dij(1);ans = 1e18;
	for(int i = 1;i <= cnt;i++)
		if(vis[i] != 2&&id[i] == n)ans = min(ans,dis[i]);
	if(ans >= 1e18)puts("-1");
	else cout<<ans;
}