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#include<bits/stdc++.h>
using namespace std;
#define fi first
#define se second
bool debug=false;
const int Q=2e5+5;
int n,m,k,q,z;
map<pair<int,int>,int>mp;
int a[Q],b[Q];
int x[Q],y[Q];
int on[Q];
int col[Q];

int dir[Q][4];
int dx[4]={-1,0,1,0};
int dy[4]={0,-1,0,1};

int sq[Q];//number of 2x2 squares formed around


vector<pair<int,int> >mem[Q];//each guy is membership of at most 4 segments

int rt[4*Q],len[4*Q];

typedef array<int,4> arin;//0 = bonus, 1 = prefix 11112, 2 = suffix 211111 ,3 = len if all 1 or 0 o/w
arin wjsn[3]={{0,0,0,0},{0,0,0,1},{0,1,1,0}};
arin merge(arin &x,arin &y){
	arin z={0,0,0,0};
	if(x[3] && y[3]){
		z[3]=x[3]+y[3];
		return z;
	}
	
	z[0]=x[0]+y[0];
	if(x[2]>0 && y[1]>0) z[0]+=x[2]+y[1]-2;
	
	if(x[3]){
		if(y[1]>0) z[1]=x[3]+y[1];
		else z[1]=0;
	}
	else z[1]=x[1];
	
	if(y[3]){
		if(x[2]>0) z[2]=x[2]+y[3];
		else z[2]=0;
	}
	else z[2]=y[2];
	return z;
}

const int ts=5e6+1;
int lc[ts],rc[ts];
arin info[ts];
int sz;
int build(int l,int r){
	int id=++sz;
	if(l==r) return id;
	int mid=(l+r)/2;
	lc[id]=build(l,mid);
	rc[id]=build(mid+1,r);
	return id;
}
void upd(int id,int l,int r,int p,int v){
	if(l==r){
		info[id]=wjsn[v];
		return;
	}
	int mid=(l+r)/2;
	if(p<=mid) upd(lc[id],l,mid,p,v);
	else upd(rc[id],mid+1,r,p,v);
	info[id]=merge(info[lc[id]],info[rc[id]]);
}
void check_sq(vector<int>v,int w){
	for(auto c:v){
		if(!on[c]) return;
	}
	/*cout << "SQuare found: ";
	for(int i=0; i<4 ;i++) cout << v[i] << ' ';
	cout << endl;*/
	for(auto c:v){
		sq[c]+=w;
	}
}

int tot_c2=0,tot_on=0;
int ans=0;
int ask(){
	//cout << "ASK: " << tot_on << ' ' << tot_c2 << ' ' << ans << endl;
	return tot_on-(tot_c2+ans);
}

void upd_col(int i,int nc){
	//cout << "upd_col " << i << ' ' << nc << endl;
	for(auto c:mem[i]){
		ans-=info[rt[c.fi]][0];
		upd(rt[c.fi],1,len[c.fi],c.se,nc);
		ans+=info[rt[c.fi]][0];
		//cout << "HI " << c.fi << ' ' << info[rt[c.fi]][0] << endl;
	}
	if(col[i]==2) tot_c2--;
	if(col[i]!=0) tot_on--;
	col[i]=nc;
	if(col[i]==2) tot_c2++;
	if(col[i]!=0) tot_on++;
}
int g[3][3];
void tog(int i){
	//cout << "tog " << a[i] << ' ' << b[i] << endl;
	g[1][1]=i;
	g[0][1]=dir[i][0];
	g[0][0]=dir[dir[i][0]][1];
	g[1][0]=dir[i][1];
	g[2][0]=dir[dir[i][1]][2];
	g[2][1]=dir[i][2];
	g[2][2]=dir[dir[i][2]][3];
	g[1][2]=dir[i][3];
	g[0][2]=dir[dir[i][3]][0];
	for(int i=0; i<2 ;i++){
		for(int j=0; j<2 ;j++){
			vector<int>v;
			for(int k=0; k<2 ;k++){
				for(int l=0; l<2 ;l++){
					v.push_back(g[i+k][j+l]);
				}
			}
			check_sq(v,-1);
		}
	}
	on[i]^=1;
	for(int i=0; i<2 ;i++){
		for(int j=0; j<2 ;j++){
			vector<int>v;
			for(int k=0; k<2 ;k++){
				for(int l=0; l<2 ;l++){
					v.push_back(g[i+k][j+l]);
				}
			}
			check_sq(v,1);
		}
	}
	for(int i=0; i<3 ;i++){
		for(int j=0; j<3 ;j++){
			if(g[i][j]==0) continue;
			int new_col=0;
			if(on[g[i][j]]) new_col=1+(sq[g[i][j]]>0);
			if(new_col!=col[g[i][j]]) upd_col(g[i][j],new_col);
		}
	}
}

bool vis[Q];
pair<int,int>val[Q];
int nxt(int id,int mode){
	if((a[id]+b[id])%2) mode^=1;
	int step;
	if(mode==0) step=3;
	if(mode==1) step=2;
	if(mode==2) step=1;
	if(mode==3) step=2;
	return dir[id][step];
}
vector<int>segs[4*Q];//for debug
void build_segs(){
	int seg_cnt=0;
	for(int mode=0; mode<4 ;mode++){
		for(int i=1; i<=z ;i++) vis[i]=false;
		if(mode==0){
			for(int i=1; i<=z ;i++){
				val[i]={a[i]+b[i],i};
			}
			sort(val+1,val+z+1);
		}
		if(mode==2){
			for(int i=1; i<=z ;i++){
				val[i]={a[i]-b[i],i};
			}
			sort(val+1,val+z+1);
		}
		for(int j=1; j<=z ;j++){
			int i=val[j].se;
			if(vis[i]) continue;
			int cur=++seg_cnt;
			int frog=i;
			for(int j=1; frog ;j++){
				len[cur]=j;
				mem[frog].push_back({cur,j});
				vis[frog]=true;
				//segs[cur].push_back(frog);
				frog=nxt(frog,mode);
			}
			rt[cur]=build(1,len[cur]);
		}
	}/*
	for(int i=1; i<=seg_cnt ;i++){
		cout << "seg " << i << ": ";
		for(auto c:segs[i]){
			cout << c << ' ';
		}
		cout << endl;
	}*/
}
int main(){
	ios::sync_with_stdio(false);cin.tie(0);
	cin >> n >> m >> k >> q;
	for(int i=1; i<=k+q ;i++){
		cin >> x[i] >> y[i];
		if(mp[{x[i],y[i]}]==0){
			mp[{x[i],y[i]}]=++z;
			a[z]=x[i];
			b[z]=y[i];
		}
	}
	for(int i=1; i<=z ;i++){
		for(int j=0; j<4 ;j++){
			int nx=a[i]+dx[j];
			int ny=b[i]+dy[j];
			if(mp[{nx,ny}]==0) mp.erase({nx,ny});
			else dir[i][j]=mp[{nx,ny}];
		}
	}
	/*for(int i=1; i<=z ;i++){
		cout << i << ' ' << a[i] << ' ' << b[i] << endl;
		cout << "DIR: ";
		for(int j=0; j<4 ;j++) cout << dir[i][j] << ' ';
		cout << endl;
	}*/
	build_segs();
	for(int i=1; i<=k ;i++) tog(mp[{x[i],y[i]}]);
	cout << ask() << '\n';
	for(int i=k+1; i<=k+q ;i++){
		tog(mp[{x[i],y[i]}]);
		cout << ask() << '\n';
	}
}