#include<bits/stdc++.h>
using namespace std;
int a[105][105];
int main(){
	int n,m,k;
	cin>>n>>m>>k;
	for(int i=1;i<=m;i++){
		int x,y;
		cin>>x>>y;
		a[x][y]=a[x-1][y]=a[x-2][y]=a[x][y+1]=a[x][y+2]=a[x][y-1]=a[x][y-2]=a[x+1][y]=a[x+2][y]=1;
		a[x-1][y-1]=a[x-1][y+1]=a[x+1][y-1]=a[x+1][y+1]=1;
	}
	for(int l=1;l<=k;l++){
		int x,y;
		cin>>x>>y;
		for(int i=x-2;i<=x+2;i++){
			for(int j=y-2;j<=y+2;j++){
				a[i][j]=1;
			}
		}
	}
	int cnt=0;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=n;j++){
			if(a[i][j]==0)cnt++;
		}
	}
	cout<<cnt;
	return 0;
}