2 5 10
2 2
1 1
1 4
2 1
1 2
1 5
2 4
2 5
1 3
2 3
 2 2 2
1 1
2 2
 3 3 9
1 1
1 2
1 3
2 1
2 2
2 3
3 1
3 2
3 3
 7 5 35
5 3
3 5
1 1
2 5
6 4
7 2
5 1
3 4
6 5
7 3
4 1
2 2
4 2
2 4
4 3
3 3
6 1
1 2
4 5
1 3
2 1
5 5
7 5
7 1
6 2
1 4
1 5
3 2
4 4
5 2
2 3
6 3
7 4
5 4
3 1
 1 5 4
1 1
1 2
1 4
1 5
 1 1 1
1 1
 5 7 21
4 4
4 5
5 5
5 6
5 7
5 1
5 2
4 2
3 2
3 1
3 7
3 6
2 6
1 6
1 7
1 1
1 2
1 3
1 4
2 4
3 4
 2 1 1
1 1
 2 2 4
2 1
1 1
1 2
2 2
 3000 3000 1
2222 738
 5 7 35
1 2
2 3
5 1
5 7
4 4
5 3
3 1
2 6
4 5
2 7
4 1
2 1
2 2
1 7
5 6
3 6
4 6
1 6
1 1
3 3
3 4
4 2
2 5
5 5
3 5
2 4
1 5
1 3
4 3
5 4
1 4
3 7
4 7
3 2
5 2
 5 4 1
4 1
 3 4 12
2 3
3 2
2 2
2 1
1 2
3 1
1 4
1 3
3 3
2 4
3 4
1 1
 3 3 3
1 1
2 2
3 3

8
 1
 6
 26
 4
 0
 20
 0
 2
 1
 28
 1
 9
 3

#include <bits/stdc++.h>
const int N = 3000 + 10, SZ = 8;
const int dx[] = {-1, -1, -1, 0, 0, 1, 1, 1},
          dy[] = {-1, 0, 1, -1, 1, -1, 0, 1};
int n, m;
int anc[N * N * 2], tag[N * N * 2];
bool flag[N][N * 2];
inline int pos(int x, int y) { return x * m * 2 + y; }
inline int Find(int p) { return anc[p] == p ? p : (anc[p] = Find(anc[p])); }
inline void Union(int u, int v) {
  u = Find(u), v = Find(v);
  if (u != v) anc[u] = v;
}
int main() {
  scanf("%d%d", &n, &m);
  if (m == 1) {
    puts("0");
    return 0;
  }
  int tcase;
  for (int x = 0; x < n; ++x) {
    for (int y = 0; y < 2 * m; ++y) {
      int p = pos(x, y);
      anc[p] = p;
    }
  }
  memset(tag, 0x3f, sizeof tag);
  int ans = 0;
  for (scanf("%d", &tcase); tcase--;) {
    int x, y;
    scanf("%d%d", &x, &y);
    --x, --y;
    for (int k = 0; k < SZ; ++k) {
      int a = x + dx[k], b = (y + dy[k] + 2 * m) % (2 * m);
      if (0 <= a && a < n && flag[a][b]) tag[Find(pos(a, b))] = tcase;
    }
    bool cur = true;
    for (int k = 0; k < SZ; ++k) {
      int a = x + dx[k], b = (y + dy[k] + 3 * m) % (2 * m);
      if (0 <= a && a < n && flag[a][b]) cur &= (tag[Find(pos(a, b))] != tcase);
    }
    if (cur) {
      ++ans;
      flag[x][y] = flag[x][y + m] = true;
      for (int gap = 0; gap <= m; gap += m) {
        for (int k = 0; k < SZ; ++k) {
          int a = x + dx[k], b = (y + dy[k] + gap + 2 * m) % (2 * m);
          if (0 <= a && a < n && flag[a][b]) Union(pos(x, y + gap), pos(a, b));
        }
      }
    }
  }
  printf("%d\n", ans);
  return 0;
}
