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#include <bits/stdc++.h>

#define ll long long
#define ve vector
#define fi first
#define se second
#define ld double
#define all(x) x.begin(), x.end()

using namespace std;

typedef pair<int, int> pii;

set<pii> a;
map<pii, int> cnt;
int ans = 0;

bool check(int x, int y)
{
    for (int dx = 0; dx <= 1; dx++)
        for (int dy = 0; dy <= 1; dy++)
            if (a.find({x + dx, y + dy}) == a.end())
                return 0;
    return 1;
}

void add(int x, int y, int a)
{
    for (int dx = 0; dx <= 1; dx++)
        for (int dy = 0; dy <= 1; dy++)
        {
            ans -= (bool)cnt[{x + dx, y + dy}];
            cnt[{x + dx, y + dy}] += a;
            ans += (bool)cnt[{x + dx, y + dy}];
        }
}

signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n, m, k, q;
    cin >> n >> m >> k >> q;
    for (int i = 0; i < k; i++)
    {
        int x, y;
        cin >> x >> y;
        a.insert({x, y});
        for (int dx = 0; dx <= 1; dx++)
            for (int dy = 0; dy <= 1; dy++)
                if (check(x - dx, y - dy))
                    add(x - dx, y - dy, 1);
    }
    cout << a.size() - ans << "\n";
    while (q--)
    {
        int x, y;
        cin >> x >> y;
        if (a.find({x, y}) == a.end())
        {
            a.insert({x, y});
            for (int dx = 0; dx <= 1; dx++)
                for (int dy = 0; dy <= 1; dy++)
                    if (check(x - dx, y - dy))
                        add(x - dx, y - dy, 1);
        }
        else
        {
            for (int dx = 0; dx <= 1; dx++)
                for (int dy = 0; dy <= 1; dy++)
                    if (check(x - dx, y - dy))
                        add(x - dx, y - dy, -1);
            a.erase({x, y});
        }
        cout << a.size() - ans << "\n";
    }
}