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#include <bits/stdc++.h>
using namespace std;
using i64 = long long;

int main() {
    int h, w, n, m;
    cin >> h >> w >> n >> m;

    int res = 0;
    map<pair<int,int>,int> tiles;

    auto has_square = [&](int x, int y) {
        for (int dx = 0; dx < 2; dx++) {
            for (int dy = 0; dy < 2; dy++) {
                if (!tiles.count(make_pair(x+dx, y+dy))) return false;
            }
        }
        return true;
    };

    auto add_square = [&](int x, int y, int delta) {
        for (int dx = 0; dx < 2; dx++) {
            for (int dy = 0; dy < 2; dy++) {
                auto pr = make_pair(x+dx, y+dy);
                if (tiles[pr] == 0) res--;
                tiles[pr] += delta;
                if (tiles[pr] == 0) res++;
            }
        }
    };

    for (int q = 0; q < n+m; q++) {
        int x, y;
        cin >> x >> y;
        auto pr = make_pair(x, y);
        if (!tiles.count(pr)) {
            tiles[pr] = 0;
            res++;
            for (int dx = 0; dx < 2; dx++) {
                for (int dy = 0; dy < 2; dy++) {
                    if (has_square(x-1+dx, y-1+dy)) {
                        add_square(x-1+dx, y-1+dy, 1);
                    }
                }
            }
        } else {
            for (int dx = 0; dx < 2; dx++) {
                for (int dy = 0; dy < 2; dy++) {
                    if (has_square(x-1+dx, y-1+dy)) {
                        add_square(x-1+dx, y-1+dy, -1);
                    }
                }
            }
            tiles.erase(pr);
            res--;
        }
        if (q >= n-1) cout << res << '\n';
    }
}