#include <bits/stdc++.h>
using namespace std;
int main(){
	ios::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
	int N; cin >> N;
	bool A[200010] = {};
	int now = 0;
	int M1; cin >> M1;
	for(int i = 0; i < M1; i++){
		int a; cin >> a; now += a; A[now] = true;
	}
	now = N;
	int M2; cin >> M2;
	for(int i = 0; i < M2; i++){
		int a; cin >> a; now -= a; A[now] = true;
	}
	int ans = 0;
	for(int i = 0; i <= N; i++){
		if(!A[i]) ans ++;
	}
	cout << ans << "\n";
}