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

int dfs(int node,int p,vector<vector<int>> &g){
    int ans=1;
    for(auto x:g[node]) {
        if(x!=p) ans+=dfs(x,node,g);
    }
    return ans;
}
int main()
{
    int n,m;
    cin>>n>>m;
    vector<vector<int>> g(n+1);
    vector<int> prim(m),dep,indegree(n+1,0);
    vector<vector<int>> edge;
    set<vector<int>> st_edge;
    for(int i=0;i<m;i++) cin>>prim[i];
    cin>>m;dep.resize(m);
    for(int i=0;i<m;i++) cin>>dep[i];
    for(int i=0;i<min(dep.size(),prim.size());i++){
        g[prim[i]].push_back(dep[i]);
        indegree[dep[i]]++;
        edge.push_back({prim[i],dep[i]});
        st_edge.insert({prim[i],dep[i]});
    }
    int ans=0;
    vector<int> vis(n+1,0);
    queue<int> q;
    for(int i=1;i<=n;i++) if(indegree[i]==0) q.push(i);
    while(!q.empty()){
        int temp=q.front();q.pop();
        ans++;
        vis[temp]=1;
        for(auto x:g[temp]){
            indegree[x]--;
            if(indegree[x]==0) q.push(x);
        }
    }
    for(auto x:edge){
        int n1=x[0],n2=x[1];
        if(vis[n1]==0 && vis[n2]==0 && st_edge.find({n2,n1})!=st_edge.end()){
            int temp = max(dfs(n1,n2,g),dfs(n2,n1,g));
            ans+=temp;
            vis[n1]=1;
            vis[n2]=1;
        }
    }
    cout<<ans<<"\n";

}