#include <iostream>
#include <vector>
#include <string>
#include <list>
#include <queue>
#include <algorithm>
#define rep(i, n) for(i = 0; i < (n); i++)
#define chmax(x, y) x = max(x, y)
#define chmin(x, y) x = min(x, y)
#define MOD 1000000007
#define PI 3.14159265358979323846
#define INF 1 << 30

using namespace std;
typedef long long ll;
typedef pair<int, int> pp;

int main(void) {
	int num, i, w, h, m, n;
	ll ans = 0;
	cin >> w >> h >> num;
	vector<int> a(w, h), b(h, w);
	vector<pp> d(num);
	rep(i, num) {
		cin >> m >> n;
		m--; n--;
		d[i] = make_pair(m, n);
		a[m]--;
		b[n]--;
	}
	rep(i, num) {
		ans += a[d[i].first] + b[d[i].second];
	}
	cout << ans << "\n";
	return 0;
}