#include<iostream>
#include<cmath>
#include<string>

using namespace std;
//#define int long long
const int maxn = 105;
int b[maxn][maxn];
int main()
{
	int n, m, k;
	cin >> n >> m >> k;
	for (int i = 1; i <= m; i++)
	{
		int x, y;
		cin >> x >> y;
		b[x][y] = 1;
		for (int j = x - 2; j <= x + 2; j++)
		{
			if (j<1 || j>n)
				continue;
			b[x][j] = 1;
		}
		for (int j = y - 2; j <= y + 2; j++)
		{
			if (j<1 || j>n)
				continue;
			b[j][y] = 1;
		}
		for (int j = x - 1; j <= x + 1; j++)
		{
			if (j<1 || j>n)
				continue;
			b[x-1][j] = 1;
			b[x + 1][j] = 1;
		}
	}
	for (int i = 1; i <= k; i++)
	{
		int o, p;
		cin >> o >> p;
		b[o][p] = 1;
		for (int j = o - 2; j <= o + 2; j++)
		{
			if (j<1 || j>n)
				continue;
			for (int kk = p - 2; kk <= p + 2; kk++)
			{
				if (kk<1 || kk>n)
					continue;
				b[j][kk] = 1;
			}
		}
	}
	int res = 0;
	for (int i = 1; i <= n; i++)
	{
		for (int j = 1; j <= n; j++)
		{
			if (b[i][j] == 0)
			{
				res++;
			}
		}
	}
	cout << res << endl;
	return 0;
}