#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
#include<numeric>
#include<cmath>
#include<utility>
#include<tuple>
#include<cstdint>
#include<cstdio>
#include<iomanip>
#include<map>
#include<queue>
#include<set>
#include<stack>
#include<deque>
#include<unordered_map>
#include<unordered_set>
#include<bitset>
#include<cctype>
#include<chrono>
#include<random>
#include<cassert>
#include<cstddef>
#include<iterator>
#include<string_view>
#include<type_traits>

#ifdef LOCAL
#  include "debug_print.hpp"
#  define debug(...) debug_print::multi_print(#__VA_ARGS__, __VA_ARGS__)
#else
#  define debug(...) (static_cast<void>(0))
#endif

using namespace std;
#define rep1(a)          for(int i = 0; i < a; i++)
#define rep2(i, a)       for(int i = 0; i < a; i++)
#define rep3(i, a, b)    for(int i = a; i < b; i++)
#define rep4(i, a, b, c) for(int i = a; i < b; i += c)
#define overload4(a, b, c, d, e, ...) e
#define rep(...) overload4(__VA_ARGS__, rep4, rep3, rep2, rep1)(__VA_ARGS__)
#define rrep1(a)          for(int i = (a)-1; i >= 0; i--)
#define rrep2(i, a)       for(int i = (a)-1; i >= 0; i--)
#define rrep3(i, a, b)    for(int i = (b)-1; i >= a; i--)
#define rrep4(i, a, b, c) for(int i = (b)-1; i >= a; i -= c)
#define rrep(...) overload4(__VA_ARGS__, rrep4, rrep3, rrep2, rrep1)(__VA_ARGS__)
#define ALL(v) v.begin(), v.end()
#define RALL(v) v.rbegin(), v.rend()
#define UNIQUE(v) v.erase( unique(v.begin(), v.end()), v.end() );
#define pb push_back
using ll = long long;
using D = double;
using LD = long double;
using P = pair<int, int>;
using vi = vector<int>;
using vl = vector<ll>;
template <class T> using vc = vector<T>;
template <class T> using vvc = vector<vc<T>>;
template <class T> using vvvc = vector<vvc<T>>;
template <class T> using vvvvc = vector<vvvc<T>>;
template <class T> using vvvvvc = vector<vvvvc<T>>;
#define vv(type, name, h, ...) \
  vector<vector<type>> name(h, vector<type>(__VA_ARGS__))
#define vvv(type, name, h, w, ...)   \
  vector<vector<vector<type>>> name( \
      h, vector<vector<type>>(w, vector<type>(__VA_ARGS__)))
#define vvvv(type, name, a, b, c, ...)       \
  vector<vector<vector<vector<type>>>> name( \
      a, vector<vector<vector<type>>>(       \
             b, vector<vector<type>>(c, vector<type>(__VA_ARGS__))))
template<typename T> using PQ = priority_queue<T,vector<T>>;
template<typename T> using minPQ = priority_queue<T, vector<T>, greater<T>>;
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }
void yesno(bool flag) {cout << (flag?"Yes":"No") << "\n";}

template<typename T, typename U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
    os << p.first << " " << p.second;
    return os;
}
template<typename T, typename U>
istream &operator>>(istream &is, pair<T, U> &p) {
    is >> p.first >> p.second;
    return is;
}

template<typename T>
ostream &operator<<(ostream &os, const vector<T> &v) {
    int s = (int)v.size();
    for (int i = 0; i < s; i++) os << (i ? " " : "") << v[i];
    return os;
}
template<typename T>
istream &operator>>(istream &is, vector<T> &v) {
    for (auto &x : v) is >> x;
    return is;
}
void in() {}
template<typename T, class... U>
void in(T &t, U &...u) {
    cin >> t;
    in(u...);
}
void out() { cout << "\n"; }
template<typename T, class... U, char sep = ' '>
void out(const T &t, const U &...u) {
    cout << t;
    if (sizeof...(u)) cout << sep;
    out(u...);
}
void outr() {}
template<typename T, class... U, char sep = ' '>
void outr(const T &t, const U &...u) {
    cout << t;
    outr(u...);
}

#include "atcoder/dsu.hpp"

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int h,w,n; in(h,w,n);
    atcoder::dsu uf(h+w);
    vv(int, has_x, h);
    vv(int, has_y, w);
    rep(i,n){
        int x,y; in(x,y); x--; y--;
        uf.merge(x,h+y);
        has_x[x].pb(y);
        has_y[y].pb(x);
    }
    // rep(i,h){
    //     int sz = has_x[i].size();
    //     rep(j, sz-1){
    //         uf.merge(has_x[i][j]+h, has_x[i][j+1]+h);
    //     }
    // }
    // rep(i,w){
    //     int sz = has_y[i].size();
    //     rep(j, sz-1){
    //         uf.merge(has_y[i][j], has_y[i][j+1]);
    //     }
    // }
    vector<P> g;
    for (vector<int> &v : uf.groups()){
        int cx = 0, cy = 0;
        for(int e : v) {
            if(e < h) cx++;
            else cy++;
        }
        g.emplace_back(cx,cy);
    }
    int k = g.size();
    int dp_max[k+1][h+1], dp_min[k+1][h+1];
    rep(i,k+1)rep(j,h+1){
        dp_max[i][j] = -1;
        dp_min[i][j] = w+1;
    }
    dp_max[0][0] = 0;
    dp_min[0][0] = 0;
    rep(i,k)rep(j,h+1) {
        auto [dx,dy] = g[i];
        if(dp_max[i][j] != -1) {
            chmax(dp_max[i+1][j], dp_max[i][j]);
            if(j+dx <= h) chmax(dp_max[i+1][j+dx], dp_max[i][j]+dy);
        }
        if(dp_min[i][j] != w+1 and j+dx <= h){
            chmin(dp_min[i+1][j], dp_min[i][j]);
            if(j+dx <= h) chmin(dp_min[i+1][j+dx], dp_min[i][j]+dy);
        }
    }
    int ans = 0;
    rep(i,h/2+1) if(dp_max[k][i] != -1){
        chmax(ans, i*w + dp_max[k][i] * (h-2*i));
    }
    rep(i,h/2+1, h+1) if(dp_min[k][i] != w+1){
        chmax(ans, i*w + dp_min[k][i] * (h-2*i));
    }
    out(ans);
}