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#include <bits/stdc++.h>
using namespace std;

#define rep(i, a, b) for (int i = (a); i < (b); i++)
#define all(x) begin(x), end(x)
#define sz(x) int((x).size())
using ll = long long;
using pii = pair<int, int>;
using vi = vector<int>;

#ifdef LOCAL
auto operator<<(auto& o, auto x) -> decltype(x.first, o);
auto operator<<(auto& o, auto x) -> decltype(x.end(), o) {
  o << "{";
  for (int i = 0; auto y : x) o << ", " + !i++ * 2 << y;
  return o << "}"; }
auto operator<<(auto& o, auto x) -> decltype(x.first, o) {
  return o << "(" << x.first << ", " << x.second << ")"; }
void __print(auto... x) { ((cerr << x << " "), ...) << endl; }
#define debug(x...) __print("[" #x "]:", x)
#else
#define debug(...) 2137
#endif

struct RollbackUF {
	vi e; vector<pii> st;
  vi c; vector<pii> sc;
  int suma = 0; vi ss;
	RollbackUF(int n) : e(n, -1), c(n, 0) {}
	int size(int x) { return -e[find(x)]; }
	int find(int x) { return e[x] < 0 ? x : find(e[x]); }
	int time() { return sz(st); }
	void rollback(int t) {
		for (int i = time(); i --> t;)
			e[st[i].first] = st[i].second;
		for (int i = time(); i --> t;)
			c[sc[i].first] = sc[i].second;
		for (int i = time(); i --> t;)
      suma = ss[i];
		st.resize(t);
    sc.resize(t);
    ss.resize(t);
	}
	bool join(int a, int b) {
		a = find(a), b = find(b);
		if (a == b) return false;
		if (e[a] > e[b]) swap(a, b);
		st.push_back({a, e[a]});
		st.push_back({b, e[b]});
    sc.push_back({a, c[a]});
    sc.push_back({b, c[b]});
    ss.push_back(suma); ss.push_back(suma);
    if (c[a]) suma -= -e[a];
    if (c[b]) suma -= -e[b];
		e[a] += e[b]; e[b] = a;
    c[a] |= c[b];
    if (c[a]) suma += -e[a];
		return true;
	}
  void wlacz(int a) {
    a = find(a);
    if (!c[a]) {
      st.push_back({a, e[a]}); st.push_back({a, e[a]});
      sc.push_back({a, c[a]}); sc.push_back({a, c[a]});
      ss.push_back(suma); ss.push_back(suma);
      suma += -e[a];
      c[a] = 1;
    }
  }
};

const int Q = 75075;
int n, m, k, q;
vi wlacz[2 * Q];
vector<pii> dodaj[2 * Q];
int odp[Q];

ll id(int i, int j) { return 1ll * m * i + j; }

map<ll, int> mp; // unordered_map
int nri(ll x) {
  if (!mp.count(x)) return mp[x] = sz(mp);
  return mp[x];
}
int nr(int i, int j) { return nri(id(i, j)); }

void wrzuc(int u, int lo, int hi, int l, int r, auto& gdzie, auto co) {
  if (l <= lo && hi <= r) {
    gdzie[u].push_back(co);
    return;
  }
  int mid = (lo + hi) / 2;
  if (l < mid) wrzuc(u + 1, lo, mid, l, r, gdzie, co);
  if (r > mid) wrzuc(u + (mid - lo) * 2, mid, hi, l, r, gdzie, co);
}

// krawedzie istnieja jezeli obaj nie sa w 2x2
// jest wlaczany jezeli ma legalny ruch

set<ll> s; // wszyscy
map<ll, int> nie, ruch; // nie w 2x2, wlaczone
void flip(int x, int y, int t) {
  auto id2 = [&](int i, int j) { return id(x - 2 + i, y - 2 + j); };
  auto nr2 = [&](int i, int j) { return nr(x - 2 + i, y - 2 + j); };
  // zczytujemy terazniejszy grid
  int g[5][5] = {};
  rep(i, 0, 5) {
    int xx = x - 2 + i;
    if (xx >= 0 && xx < n) {
      auto it = s.lower_bound(id(xx, max(0, y - 2)));
      while (it != s.end()) {
        int xi = *it / m, yi = *it % m;
        if (xi != xx || yi > min(m - 1, y + 2)) break;
        g[i][yi - (y - 2)] = 1;
        it++;
      }
    }
  }
  // zczytujemy od kiedy nie sa czescia kwadratu 2x2
  int dwa[5][5];
  rep(i, 0, 5) rep(j, 0, 5) dwa[i][j] = -1;
  rep(i, 0, 5) {
    int xx = x - 2 + i;
    if (xx >= 0 && xx < n) {
      auto it = nie.lower_bound(id(xx, max(0, y - 2)));
      while (it != nie.end()) {
        int xi = it->first / m, yi = it->first % m;
        if (xi != xx || yi > min(m - 1, y + 2)) break;
        dwa[i][yi - (y - 2)] = it->second;
        it++;
      }
    }
  }
  // zczytujemy czy moga zrobic ruch
  bool czy[5][5] = {};
  rep(i, 1, 4) rep(j, 1, 4) if (g[i][j]) {
    czy[i][j] = (!g[i - 1][j] && !g[i + 1][j]) || (!g[i][j - 1] && !g[i][j + 1]);
  }
  // flip
  int g2[5][5] = {};
  rep(i, 0, 5) rep(j, 0, 5) g2[i][j] = g[i][j];
  g2[2][2] ^= 1;
  // czy po flipie jest w kwadr 2x2
  bool dwa2[5][5] = {};
  rep(i, 0, 4) rep(j, 0, 4) {
    if (g2[i][j] + g2[i + 1][j] + g2[i][j + 1] + g2[i + 1][j + 1] == 4) {
      dwa2[i][j] = dwa2[i + 1][j] = dwa2[i][j + 1] = dwa2[i + 1][j + 1] = 1;
    }
  }
  rep(i, 0, 5) {
    if (dwa[i][0] == -1) dwa2[i][0] = 1;
    if (dwa[0][i] == -1) dwa2[0][i] = 1;
    if (dwa[i][4] == -1) dwa2[i][4] = 1;
    if (dwa[4][i] == -1) dwa2[4][i] = 1;
  }
  // czy po flipie moze zrobic ruch
  bool czy2[5][5] = {};
  rep(i, 1, 4) rep(j, 1, 4) if (g2[i][j]) {
    czy2[i][j] = (!g2[i - 1][j] && !g2[i + 1][j]) || (!g2[i][j - 1] && !g2[i][j + 1]);
  }
  // porownojemy
  // poziome
  rep(i, 1, 4) rep(j, 0, 4) {
    bool wcz = g[i][j] && g[i][j + 1] && dwa[i][j] != -1 && dwa[i][j + 1] != -1;
    bool ter = g2[i][j] && g2[i][j + 1] && !dwa2[i][j] && !dwa2[i][j + 1];
    if (wcz && !ter) {
      int kiedy = max(dwa[i][j], dwa[i][j + 1]);
      wrzuc(0, 0, q, kiedy, t, dodaj, pii(nr2(i, j), nr2(i, j + 1)));
    }
  }
  // pionowe
  rep(i, 0, 4) rep(j, 1, 4) {
    bool wcz = g[i][j] && g[i + 1][j] && dwa[i][j] != -1 && dwa[i + 1][j] != -1;
    bool ter = g2[i][j] && g2[i + 1][j] && !dwa2[i][j] && !dwa2[i + 1][j];
    if (wcz && !ter) {
      int kiedy = max(dwa[i][j], dwa[i + 1][j]);
      wrzuc(0, 0, q, kiedy, t, dodaj, pii(nr2(i, j), nr2(i + 1, j)));
    }
  }
  // updatujemy nie
  rep(i, 1, 4) rep(j, 1, 4) {
    bool wcz = g[i][j] && dwa[i][j] != -1;
    bool ter = g2[i][j] && !dwa2[i][j];
    if (wcz && !ter) {
      nie.erase(id2(i, j));
    } else if (!wcz && ter) {
      //debug(x - 2 + i, y - 2 + j);
      nie[id2(i, j)] = t;
    }
  }
  // ruchy
  rep(i, 1, 4) rep(j, 1, 4) {
    if (czy[i][j] == 0 && czy2[i][j] == 1) {
      ruch[id2(i, j)] = t;
    } else if (czy[i][j] == 1 && czy2[i][j] == 0) {
      wrzuc(0, 0, q, ruch[id2(i, j)], t, wlacz, nr2(i, j));
      ruch.erase(id2(i, j));
    }
  }
  if (s.contains(id(x, y))) s.erase(id(x, y));
  else s.insert(id(x, y));
}

RollbackUF uf(0);

void dfs(int u, int lo, int hi) {
  int t = uf.time();
  for (auto [i, j] : dodaj[u]) uf.join(i, j);
  for (int i : wlacz[u]) uf.wlacz(i);
  for (int i : wlacz[u]) uf.wlacz(i);
  if (lo + 1 == hi) {
    odp[lo] = uf.suma;
    uf.rollback(t);
    return;
  }
  int mid = (lo + hi) / 2;
  dfs(u + 1, lo, mid);
  dfs(u + (mid - lo) * 2, mid, hi);
  uf.rollback(t);
}

int main() {
  cin.tie(0)->sync_with_stdio(0);
  cin >> n >> m >> k >> q;
  q++;
  rep(i, 0, k) {
    int x, y;
    cin >> x >> y;
    x--; y--;
    flip(x, y, 0);
  }
  rep(i, 1, q) {
    int x, y;
    cin >> x >> y;
    x--; y--;
    flip(x, y, i);
  }
  for (auto [i, j] : ruch) wrzuc(0, 0, q, j, q, wlacz, nri(i));
  for (auto [i, j] : nie) {
    int x = i / m, y = i % m;
    rep(dx, -1, 2) rep(dy, -1, 2) if (abs(dx) + abs(dy) == 1) {
      int u = x + dx, v = y + dy;
      if (u >= 0 && u < n && v >= 0 && v < m) {
        ll ii = id(u, v);
        if (nie.count(ii)) {
          int kiedy = max(j, nie[ii]);
          wrzuc(0, 0, q, kiedy, q, dodaj, pii(nr(x, y), nr(u, v)));
        }
      }
    }
  }
  uf = RollbackUF(sz(mp));
  dfs(0, 0, q);
  rep(i, 0, q) cout << odp[i] << '\n';
}