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#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
const int MAXN=2e5;
const int MAXK=75000;

int n,m;
int ile=0;
map<int, bool> M[MAXN+5];
map<int, int> usuwalne[MAXN+5];
set<pair<int,int>> points;

int ans=0;
int tur=1;

bool check1(int x, int y)
{
	if(!M[x-1][y] && !M[x+1][y]) return 1;
	if(!M[x][y-1] && !M[x][y+1]) return 1;
	return 0;
}

bool check2(int x, int y)
{
	if((!M[x-1][y] || usuwalne[x-1][y]==tur) && (!M[x+1][y] || usuwalne[x+1][y]==tur)) return 1;
	if((!M[x][y-1] || usuwalne[x][y-1]==tur) && (!M[x][y+1] || usuwalne[x][y+1]==tur)) return 1;
	return 0;
}

void bf()
{
	for(int i=1;i<=ile;i++){
		bool zmiana=0;
		for(pair<int,int> pr : points){
			int x = pr.first;
			int y = pr.second;
			if(check2(x, y)){
				if(usuwalne[x][y]==tur) continue;
				usuwalne[x][y]=tur;
				ans++;
				zmiana=1;
			}
		}
		if(!zmiana) break;
	}
}

void solve()
{
	cin >> n >> m;
	int k,q;
	cin >> k >> q;
	ile=k;
	for(int i=0;i<k;i++){
		int x,y;
		cin >> x >> y;
		M[x][y]=1;
		points.insert({x,y});
	}
	bf();
	tur++;
	cout << ans << "\n";
	for(int i=0;i<q;i++){
		int x,y;
		cin >> x >> y;
		if(M[x][y]) points.erase({x,y});
		else points.insert({x,y});
		M[x][y]^=1;
		if(M[x][y]) ile++;
		else ile--;
		
		ans=0;
		bf();
		tur++;
		cout << ans << "\n";
	}
}

int main()
{
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	solve();
	
	return 0;
}