#include <iostream>
#include <algorithm>
#include <queue>
using namespace std;

long long n,m1,m2,mans=-1;
struct hb{
	long long arr,lef;
	bool operator<(hb a)const{
		return a.lef<lef;
	}
}hb1s[100005],hb2s[100005];



bool cmp(hb hb1,hb hb2){
	return hb1.arr<hb2.arr;
}

priority_queue<hb> a,b;

int main(){
	scanf("%lld%lld%lld",&n,&m1,&m2);
	for (int i=1;i<=m1;i++){
		scanf("%lld%lld",&hb1s[i].arr,&hb1s[i].lef);
	}
	for (int i=1;i<=m2;i++){
		scanf("%lld%lld",&hb2s[i].arr,&hb2s[i].lef);
	}
	sort(hb1s+1,hb1s+1+m1,cmp);
	sort(hb2s+1,hb2s+1+m1,cmp);
	for (int i=0;i<=n;i++){
		long long li=i,lj=n-i,ans=0;
		for (int k=1;k<=m1;k++){
			while (!a.empty()&&hb1s[k].arr>a.top().lef){
				a.pop();
				li++;
			}
			if (li>0){
				a.push(hb1s[k]);
				ans++;
				li--;
			}
		}
		for (int k=1;k<=m2;k++){
			while (!b.empty()&&hb2s[k].arr>b.top().lef){
				b.pop();
				lj++;
			}
			if (lj>0){
				b.push(hb2s[k]);
				ans++;
				lj--;
			}
		}
		mans=max(ans,mans);
	}
	printf("%lld",mans);
	return 0;
}