#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using ull = unsigned long long;

const int N = 1e5 + 5;
const int Inf = 1e19 + 7;
int n, m, k;
int maxn(0), minn(0), cur(0);
int a[N];

void Read()
{
    cin >> n >> m >> k;
    while (m--)
    {
        int v;
        cin >> v;
        if (v == 1)
            --cur;
        else
            ++cur;
        minn = min(minn, cur);
        maxn = max(maxn, cur);
    }
    for (int i = 1; i <= k; ++i)
        cin >> a[i];
    a[0] = 0;
    a[k + 1] = n + 1;
}

void Solve()
{
    int ans(0);
    for (int i = 1; i <= k + 1; ++i)
        ans += max(0, a[i] - maxn - 1 - (a[i - 1] + abs(minn) + 1) + 1);
    cout << ans;
}

int32_t main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    Read();
    Solve();
}