// Source: https://usaco.guide/general/io

#include <bits/stdc++.h>
using namespace std;
#define int long long
const int INF=1e12;

signed main() {
    int n,k,q;cin>>n>>k>>q;
    vector<int> v(n);
    for(int i = 0;i<n;i++){
        cin>>v[i];
    }
    vector<pair<int,int>> que(q);
    for(auto&[a,b]:que)cin>>a>>b;
    int l=-1,m,h=n;
    while(l<h-1){
        m=(l+h)/2;
        int ind=m;
        bool jo=false;
        for(auto[a,b]:que){
            if(v[ind]==a)ind+=b;
            if(ind==-1||ind==n){
                jo=ind==-1;
                break;
            }
        }
        if(jo){
            l=m;
        }
        else{
            h=m;
        }
    }
    int bal=l;
    h=-1,l=n;
    while(h+1<l){
        m=(l+h)/2;
        int ind=m;
        bool jo=false;
        for(auto[a,b]:que){
            if(v[ind]==a)ind+=b;
            if(ind==n||ind==-1){
                jo=ind==n;
                break;
            }
        }
        if(jo){
            l=m;
        }
        else{
            h=m;
        }
    }
    int jobb=l;
    if(jobb==n&&bal==-1)cout<<0<<endl;
    else if(jobb==n){
        cout<<bal+1<<endl;
    }
    else if(bal==-1){
        cout<<n-jobb<<endl;
    }
    else cout<<n-jobb+bal+1<<endl;
}