Gopher II

#include <bits/stdc++.h>
#define fi first
#define se second

using namespace std;
using ftype = long double;

const ftype eps = 1e-9;

int n, k;

vector<vector<int>> gr;
vector<int> mt;
vector<bool> used;

bool try_kuhn(int v) {
    if (used[v]) return false;
    used[v] = true;
    for (int to : gr[v]) {
        if (mt[to] == -1 or try_kuhn(mt[to])) {
            mt[to] = v;
            return true;
        }
    }
    return false;
}

ftype getDistance(ftype a, ftype b, ftype c, ftype d) {
  return sqrtl((a - c) * (a - c) + (b - d) * (b - d));
}

int main() {

  int s, v;
  while (cin >> n >> k >> s >> v and n) {
    vector<pair<ftype, ftype>> coord, coordHoles;

    gr.assign(n + k, vector<int>());
    used.assign(n + k, false);

    for (int i = 0; i < n; ++i) {
      ftype a, b; cin >> a >> b;
      coord.push_back({a, b});
    }

    for (int i = 0; i < k; ++i) {
      ftype a, b; cin >> a >> b;
      coordHoles.push_back({a, b});
    }

    for (int i = 0; i < n; ++i) {
      for (int j = 0; j < k; ++j) {
        ftype distance = getDistance(coord[i].fi, coord[i].se, coordHoles[j].fi, coordHoles[j].se);
        if (distance <= (ftype)s * v+eps) {
          gr[i].push_back(n + j);
          gr[n + j].push_back(i);
        }
      }
    }

    mt.assign(n + k, -1);
    vector<bool> used1(n, false);

    for (int v = 0; v < n; ++v) {
      for (int to : gr[v]) {
        if (mt[to] == -1) {
          mt[to] = v;
          used1[v] = true;
          break;
        }
      }
    }

    int cnt = 0;
    for (int v = 0; v < n + k; ++v) {
      if (used1[v]) continue;
      used.assign(n + k, false);
      int r = try_kuhn(v);
      // cout << r << '\n';
      cnt += r;
    }

    // for (int i = 0; i < n + k; ++i)
    //   if (mt[i] != -1)
    //     cout << mt[i] << ' ' << i << '\n';

    // cout << cnt << '\n';
    cout << max(0, n-cnt) << '\n';
  }

}