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#include <iostream>
#include <map>
#include <utility>

using namespace std;

int n, m, k, q;
map<pair<int,int>, bool> blocks;

bool square(int x, int y, int row, int col) {
	bool flag = true;
	
	for(int i : {x, x+row}) {
		for(int j : {y, y+col}) {
			if(blocks.find( {i, j} ) == blocks.end()) {
				flag = false;
			}
		}
	}
	
	return flag;
}

bool ok(int x, int y) {
	bool flag = true;
	
	for(int i : {1, -1}) {
		for(int j : {1, -1}) {
			if(square(x, y, i, j)) {
				flag = false;
			}
		}
	}
	return flag;
}

int check9(int x, int y) {
	int cnt = 0;
	for(int row = x-1; row <= x+1; row++) {
		for(int col = y-1; col <= y+1; col++) {
			if(ok(row, col) && (blocks.find( {row, col} ) != blocks.end())) {
				cnt++;
			}
		}
	}
	return cnt;
}

int solve() {
	int cnt = 0;
	for(auto bl : blocks) {
		if(ok(bl.first.first, bl.first.second)) {
			cnt++;
		}
	}
	return cnt;
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	
	cin >> n >> m >> k >> q;
	
	for(int i = 0; i < k; i++) {
		int x, y;
		cin >> x >> y;
		blocks[ {x, y} ] = true;
	}
	
	int ans = solve();
	cout << ans << "\n";

	for(int i = 0; i < q; i++) {
		int a, b;
		cin >> a >> b;
		
		int last_check = check9(a, b);
		
		if(blocks.find( {a, b} ) == blocks.end()) {
			blocks[ {a, b} ] = true;
		}
		else {
			blocks.erase( {a, b} );
		}
		
		int new_check = check9(a, b);
		int diff = new_check - last_check;
		
		ans += diff;
		
		cout << ans << "\n";
	}

	return 0;
}