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

int ans;

map<pair<int, int>, int> all_nodes; 
map<pair<int, int>, int> update; 

bool check(int a, int b, int moment = 0){
    if(all_nodes.find({a, b}) == all_nodes.end()){
        return true;
    }
    if(all_nodes[{a, b}] == 0 and moment <= update[{a, b}]){
        return true;
    }
    if(all_nodes[{a, b}] == 1 and moment <= update[{a, b}]){
        return false;
    }
    update[{a, b}] = moment;
    bool zero = false;
    if(all_nodes[{a, b}] == 0){
        zero = true;
        ans--;
    }
    all_nodes[{a, b}] = 1;

    if(check(a+1, b, moment) and check(a-1, b, moment)){
        if(all_nodes[{a, b}] == 1){
            ans++;
        }
        check(a, b+1, moment);
        check(a, b-1, moment);
        all_nodes[{a, b}] = 0;
        update[{a, b}] = moment;
        return true;
    }
    if(check(a, b+1, moment) and check(a, b-1, moment)){
        if(all_nodes[{a, b}] == 1){
            ans++;
        }
        check(a+1, b, moment);
        check(a-1, b, moment);
        all_nodes[{a, b}] = 0;
        update[{a, b}] = moment;
        return true;
    }
    if(zero){
        check(a+1, b, moment);
        check(a-1, b, moment);
        check(a, b+1, moment);
        check(a, b-1, moment);
    }

    // if(all_nodes[{a, b}] == 0){
    //     ans--;
    // }
    all_nodes[{a, b}] = 1;
    update[{a, b}] = moment;
    return false;
}


int main(){
    int n_board, m_board;
    cin >> n_board >> m_board;

    int q;
    int n;
    cin >> n >> q;
    ans = 0;
    //ans = n;
    vector<pair<int, int>> repeat;
    for(int i = 0; i < n; i++){
        int a, b;
        cin >> a >> b;
        repeat.push_back({a, b});
        all_nodes[{a, b}] = 1;
        update[{a, b}] = -1;
    }
    for(auto [a, b]: repeat){
        check(a, b);
    }
    cout << ans << '\n';

    for(int t = 1; t <= q; t++){
        int a, b;
        cin >> a >> b;
        if(all_nodes.find({a, b}) == all_nodes.end()){
            all_nodes[{a, b}] = 1;
            update[{a, b}] = -1;
            check(a, b, t);
        }else{
            if(all_nodes[{a, b}] == 0){
                ans--;
            }
            all_nodes.erase({a, b});
            update.erase({a, b});
            check(a+1, b, t);
            check(a-1, b, t);
            check(a, b+1, t);
            check(a, b-1, t);
        }
        cout << ans << '\n';
    }



    return 0;
}