typedef long long ll;
typedef long double ld;

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

signed main(){
    ll n;
    std::cin >> n;
    ll m;
    std::cin >> m;
    vector<bool> done(n+1);
    ll now = 0;
    done[0]  = done[n] = true;
    for (int i = 0; i < m; i++) {
        ll t;
        std::cin >> t;
        now += t;
        done[now]=true;
    }
    std::cin >> m;
    for (int i = 0; i < m; i++) {
        ll t;
        std::cin >> t;
        now -= t;
        done[now]=true;
    }
    ll cnt = 0;
    for (int i = 0; i <= n; i++) {
        if(done[i])cnt++;
    }
    std::cout << n+1-cnt << std::endl;
};