/**
 * @author nhuang685
 * @date 2023-04-02 19:42:00
 */
#include <bits/stdc++.h>

using namespace std;

const array<int, 4> dx{-1, 0, 1, 0}, dy{0, 1, 0, -1};

int main() {
  ios::sync_with_stdio(false);

#ifdef LOCAL
  // freopen("input.txt", "r", stdin);
  freopen("output.txt", "w", stdout);
  // freopen("log.txt", "w", stderr);
#else
  cin.tie(nullptr);
#endif

  int n, m;
  cin >> n >> m;
  int r2;
  cin >> r2;
  pair<int, int> s;
  cin >> s.first >> s.second;

  int k;
  cin >> k;
  vector<vector<int>> grid(n + 1, vector<int>(n + 1, (int)4e18));
  for (int i = 0; i < k; ++i) {
    int x, y;
    cin >> x >> y;
    // x--;
    // y--;
    grid[x][y] = 0;
  }

  auto bfs = [&](queue<pair<int, int>> q) {
    while (!q.empty()) {
      auto [x, y] = q.front();
      q.pop();
      for (int d = 0; d < 4; ++d) {
        int a = x + dx[d], b = y + dy[d];
        if (a > 0 && a <= n && b > 0 && b <= n && grid[a][b] > grid[x][y] + 1) {
          grid[a][b] = grid[x][y] + 1;
          q.push({a, b});
        }
      }
    }
  };

  for (int i = 1; i <= n; ++i) {
    queue<pair<int, int>> q;
    for (int j = 1; j <= n; ++j) {
      if (grid[i][j] == 0) q.push({i, j});
    }
    bfs(q);
  }
  // for (int i = 1; i <= n; ++i) {
  //   for (int j = 1; j <= n; ++j) {
  //     cout << grid[i][j] << '\t';
  //   }
  //   cout << '\n';
  // }

  auto sqt = [](int a) {
    int l = 0, r = a;
    while (l < r) {
      int mid = (l + r) / 2;
      if (mid * mid >= a)
        r = mid;
      else
        l = mid + 1;
    }
    return l;
  };

  vector<vector<int>> over(n + 2, vector<int>(n + 2));
  for (int i = 1; i <= n; ++i) {
    for (int j = 1; j <= n; ++j) {
      if (r2 <= grid[i][j] * grid[i][j]) continue;
      int d = sqt(r2 - grid[i][j] * grid[i][j]);
      // i - d + 1, i + d - 1
      over[max(1, i - d + 1)][j] += 1;
      over[min(n + 1, i + d)][j] -= 1;
    }
  }
  for (int i = 1; i <= n; ++i) {
    for (int j = 1; j <= n; ++j) {
      over[i][j] += over[i - 1][j];
    }
  }
  // for (int i = 1; i <= n; ++i) {
  //   for (int j = 1; j <= n; ++j) {
  //     cout << over[i][j] << '\t';
  //   }
  //   cout << '\n';
  // }

  vector<vector<bool>> v(n + 1, vector<bool>(n + 1));
  auto dfs = [&](auto &self, int a, int b) -> int {
    v[a][b] = true;
    int ans = 1;
    for (int d = 0; d < 4; ++d) {
      int i = a + dx[d], j = b + dy[d];
      if (i * i >= r2 && (n - i + 1) * (n - i + 1) >= r2 && j * j >= r2 &&
          (n - j + 1) * (n - j + 1) >= r2 && over[i][j] == 0 && !v[i][j])
        ans += self(self, i, j);
    }
    return ans;
  };
  cout << dfs(dfs, s.first, s.second) << '\n';
}