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#include <bits/stdc++.h>
using namespace std;
#define REP(i,a,b) for (int i = (a); i <= (b); ++i)
#define REPD(i,a,b) for (int i = (a); i >= (b); --i)
#define FORI(i,n) REP(i,1,n)
#define FOR(i,n) REP(i,0,int(n)-1)
#define mp make_pair
#define pb push_back
#define pii pair<int,int>
#define vi vector<int>
#define ll long long
#define SZ(x) int((x).size())
#define DBG(v) cerr << #v << " = " << (v) << endl;
#define FOREACH(i,t) for (typeof(t.begin()) i=t.begin(); i!=t.end(); i++)
#define fi first
#define se second

const int N = 150100;
const int dx[5] = {0, 1, 0, -1, 0};
const int dy[5] = {1, 0, -1, 0, 1};

int n;
pii t[N], pt[N];
int id[N];
map<pii, int> lookup;

bool used[N];
int vis[N];
int neib[2][N];

int ans;

vector<pii> g[N];

void print_out() {
	printf("%d\n", ans);
}

void dfs_out(int u) {
	vis[u] = -1;
	ans++;
	FOR(i,SZ(g[u])) {
		int v = g[u][i].fi, c = g[u][i].se;
		if (!vis[v]) {
			neib[c][v]--;
			if (neib[c][v] == 0) {
				dfs_out(v);
			}
		}
	}
}

void queries(int lo) {
	FOR(i,n) {
		used[i] = 0;
		vis[i] = 0;
		neib[0][i] = neib[1][i] = 0;
		g[i].clear();
	}
	ans = 0;
	FOR(i,lo) used[id[i]] ^= 1;
	FOR(i,n) if (used[i]) {
		FOR(k,4) {
			pii p = pt[i];
			p.fi += dx[k];
			p.se += dy[k];
			if (lookup.find(p) != lookup.end()) {
				int j = lookup[p];
				if (used[j]) {
					g[i].pb(mp(j,k&1));
					neib[k&1][i]++;
				}
			}
		}
	}
	/*FOR(u,n) {
		printf("%d : ", u);
		FOR(i,SZ(g[u])) {
			printf("%c%d ", g[u][i].se==0?'-':'+', g[u][i].fi);
		}
		printf("\n");
	}*/
	FOR(u,n) if (used[u]) if (!vis[u]) {
		if (neib[0][u] == 0 || neib[1][u] == 0) dfs_out(u);
	}
	printf("%d\n", ans);
}

int main() {
	int nn,mm,k,q;
	scanf("%d%d%d%d", &nn, &mm, &k, &q);
	FOR(i,k+q) {
		scanf("%d%d", &t[i].fi, &t[i].se);
		if (lookup.find(t[i]) == lookup.end()) lookup[t[i]] = n++;
		id[i] = lookup[t[i]];
		pt[id[i]] = t[i];
	}
	FOR(i,q+1) queries(k+i);
	return 0;
}