#include <bits/stdc++.h>

using namespace std;
using ll = long long;

int main(){

    ll N, M, A, S, ans=0;
    cin >> N;
    vector<bool> v(N+1);
    cin >> M;
    S = 0;
    for (int i=0; i<M; i++){
        cin >> A;
        S += A;
        v[S] = 1;
    }
    cin >> M;
    S = 0;
    for (int i=0; i<M; i++){
        cin >> A;
        S += A;
        v[S] = 1;
    }

    v[0] = 1;

    for (int i=0; i<=N; i++){
        if (!v[i]) ans++;
    }

    cout << ans << endl;

    return 0;
}