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#include<bits/stdc++.h>

int n, m, k, q;

const int dx[8] = {1, 1, 1, 0, 0, -1, -1, -1};
const int dy[8] = {-1, 0, 1, -1, 1, -1, 0, 1};

void SolveFast(){
	std::map<std::pair<int, int>, int> mapka;
	std::map<std::pair<int, int>, int> is;
	
	int ans = 0;
	auto Check = [&](int x, int y)->void{
		int f = 0;
		f |= mapka[{x, y + 1}] & mapka[{x + 1, y}] & mapka[{x + 1, y + 1}];
		f |= mapka[{x, y - 1}] & mapka[{x + 1, y}] & mapka[{x + 1, y - 1}];
		f |= mapka[{x, y + 1}] & mapka[{x - 1, y}] & mapka[{x - 1, y + 1}];
		f |= mapka[{x, y - 1}] & mapka[{x - 1, y}] & mapka[{x - 1, y - 1}];
		if(f && !is[{x, y}]) --ans;
		if(!f && is[{x, y}]) ++ans;
		is[{x, y}] = f;
	};
	
	for(int i = 0;i < k;i++){
		int x, y;
		std::cin >> x >> y;
		mapka[{x, y}] = 1;
		++ans;
		Check(x, y);
		for(int d = 0;d < 8;d++){
			int nx = x + dx[d];
			int ny = y + dy[d];
			if(mapka[{nx, ny}] == 1)
				Check(nx, ny);
		}
	}
	
	std::cout << ans << '\n';
	for(int i = 0;i < q;i++){
		int x, y;
		std::cin >> x >> y;
		if(mapka[{x, y}] == 1){
			mapka[{x, y}] = 0;
			if(is[{x, y}] == 0) --ans;
			is[{x, y}] = 0;
			for(int d = 0;d < 8;d++){
				int nx = x + dx[d];
				int ny = y + dy[d];
				if(mapka[{nx, ny}] == 1)
					Check(nx, ny);
			}
		} else {
			mapka[{x, y}] = 1;
			++ans;
			Check(x, y);
			for(int d = 0;d < 8;d++){
				int nx = x + dx[d];
				int ny = y + dy[d];
				if(mapka[{nx, ny}] == 1)
					Check(nx, ny);
			}
		}
		std::cout << ans << '\n';
	}
}

int main(){
	using namespace std;
	ios::sync_with_stdio(false), cin.tie(nullptr);
	
	cin >> n >> m >> k >> q;
	
	SolveFast();
	
	return 0;
}