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#include<bits/stdc++.h>
using namespace std;

#define p pair<int, int>

const int MAXK = 75e3 + 7;
map<p, int> is_pkt; 

bool spr(p pkt){
    if(!is_pkt[pkt]) return 0;
    int x = pkt.first, y = pkt.second;
    if(!is_pkt[{x + 1, y}] && !is_pkt[{x - 1, y}]) return 1;
    if(!is_pkt[{x, y + 1}] && !is_pkt[{x, y - 1}]) return 1;
    return 0;
}

int querry(vector<p> &points, int k){
    queue<pair<int, int>> qu;

    for(int i = 0; i < k; i++){
        if(spr(points[i])){
            is_pkt[points[i]] = 0;
            qu.push(points[i]);
        }
    }

    vector<int> pion = {1, 0, -1, 0};
    vector<int> poz = {0, -1, 0, 1};

    int wyn = 0;

    while(!qu.empty()){
        p act = qu.front();
        qu.pop();
        is_pkt[act] = 0;
        wyn++;
        int x = act.first, y = act.second;
        for(int i = 0; i < 4; i++){
            int nx = x + pion[i], ny = y + poz[i];
            if(spr({nx, ny})){
                is_pkt[{nx, ny}] = 0;
                qu.push({nx, ny});
            }
        }
    }
    return wyn;
}

int main(){
    ios_base::sync_with_stdio(0);cin.tie(0);
    int n, m, k, q;
    cin >> n >> m >> k >> q;

    vector<p> points(k);

    for(int i = 0; i < k; i++){
        int x, y;
        cin >> x >> y;
        points[i] = {x, y};
        is_pkt[{x, y}] = 1;
    }

    cout << querry(points, k) << '\n';

    for(int i = 0; i < k; i++){
        is_pkt[points[i]] = 1;
    }

    int x, y;
    cin >> x >> y;
    is_pkt[{x, y}] ^= 1;

    cout << querry(points, k) << '\n';

    // bitset<MAXK> visited;

    // cout << wyn << '\n';
}