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#include <bits/stdc++.h>
#define fi first
#define sc second
#define pb push_back
#define rep(i,p,k) for(int i=(p);i<(k);++i)
#define forn(i,p,k) for(int i=(p);i<=(k);++i)
#define forr(i,k,p) for(int i=(k)-1;i>=(p);--i)
#define each(a,b) for(auto&a:b)
#define all(v)  begin(v), end(v)
#define RET(smth)   return void(cout<<(smth)<<'\n');
#define sz(v) (int)v.size()
using namespace std;
using pii = pair<int,int>;
using ll = long long;
using lll = __int128_t;
using Vi = vector<int>;
#ifdef DEBUG
#include "debug.h"
#else
#define debug(...) ;
#endif

struct hsh {
    size_t operator()(pii x) const {
        return 1ll*x.fi*200013 + x.sc;
    }
};


unordered_set<pii, hsh> S;

bool rem(int x) {
    return (x&12) == 0 || (x&3) == 0;
}

int sim() {
    int res = 0;
    unordered_map<pii, int, hsh> C;
    vector<pii> toe, tmp;
    for(auto [x, y] : S) {
        int d = S.count({x-1,y})*8 + S.count({x+1,y})*4 + S.count({x,y-1})*2 + S.count({x,y+1});
        debug(x,y,d);
        if(rem(d)) toe.emplace_back(x,y);
        else C.emplace(pii{x,y}, d);
    }
    debug(toe);
    debug(C);
    auto handle = [&](int x, int y, int dr) {
        auto it = C.find({x,y});
        if(it == C.end()) return;
        int &d = it->second;
        if(rem(d)) return;
        d -= dr;
        if(rem(d)) tmp.emplace_back(x,y);
    };
    for(;!toe.empty();toe.swap(tmp), tmp.clear()) {
        for(auto [x,y] : toe) {
            res++;
            handle(x+1,y,8);
            handle(x-1,y,4);
            handle(x,y+1,2);
            handle(x,y-1,1);
            debug(x,y,C);
        }
    }
    return res;
}

int main() {
#ifndef DEBUG
    cin.tie(0) -> sync_with_stdio(0);
#endif
    int n,m,k,q; cin >> n >> m >> k >> q;
    rep(i,0,k) {
        int x,y; cin >> x >> y;
        S.insert({x,y});
    }
    cout << sim() << '\n';
    rep(i,0,q) {
        int x,y; cin >> x >> y;
        auto it = S.find({x,y});
        if(it == S.end()) {
            S.insert({x,y});
        } else {
            S.erase(it);
        }
        cout << sim() << '\n';
    }
    return 0;
}