#include <bits/stdc++.h>

using ll = long long;
using namespace std;

const int MAXN = 100'002;

int c[MAXN], n, k, m;
vector<pair<int, int>> v;

bool f(int pos, int border) {
    for (auto [a, b] : v) {
        if (c[pos] == a) pos += b;
        if (pos <= border && border == 0) return true;
        if (pos >= border && border == n+1) return true;
    }
    return false;
}

void solve() {
    cin >> n >> k >> m;
    v.resize(m);
    for (int i = 1; i <= n; i++) cin >> c[i];
    for (auto &[a, b] : v) {
        cin >> a >> b;
    }
    int ans = 0;
    {
        int lo = 0, hi = n;
        while (lo < hi) {
            int mid = (lo + hi + 1) / 2;
            if (f(mid, 0)) lo = mid;
            else hi = mid - 1;
        }
        ans += lo;
    }
    {
        int lo = 0, hi = n;
        while (lo < hi) {
            int mid = (lo + hi) / 2;
            if (f(mid, n+1)) hi = mid;
            else lo = mid + 1;
        }
        ans += n-lo+1;
    }
    cout << ans << "\n";
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    int t = 1;
    // cin >> t;
    while (t--) {
        solve();
    }
    return 0;
}