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>
int n, m, q, ans;
int fa[(3010) * (3010)];
std::pair<int, int> seg[(3010) * (3010)];
bool vis[(3010)][(3010)];
int dir[8][2] = {{-1, -1}, {-1, 0}, {-1, 1}, {0, -1},
                 {0, 1},   {1, -1}, {1, 0},  {1, 1}};
int getfather(int x) { return fa[x] == x ? x : fa[x] = getfather(fa[x]); }
int main() {
  scanf("%d%d%d", &n, &m, &q);
  for (int i = 1; i <= n; ++i) {
    for (int j = 1; j <= m; ++j) {
      fa[(((i)-1) * m + (j))] = (((i)-1) * m + (j));
      seg[(((i)-1) * m + (j))] = {j, j};
    }
  }
  while (q--) {
    int x, y;
    scanf("%d%d", &x, &y);
    vis[x - 1][y - 1] = true;
    int left = y, right = y;
    for (int k = 0; k < 8; ++k) {
      int dx = x - 1 + dir[k][0], dy = (y - 1 + dir[k][1] + m) % m;
      if (dx < 0 || dx >= n || !vis[dx][dy]) continue;
      int u = getfather((((dx + 1) - 1) * m + (dy + 1)));
      left = std::min(left, seg[u].first);
      right = std::max(right, seg[u].second);
    }
    if (right - left + 1 >= m) {
      vis[x - 1][y - 1] = false;
      continue;
    }
    ++ans;
    for (int k = 0; k < 8; ++k) {
      int dx = x - 1 + dir[k][0], dy = (y - 1 + dir[k][1] + m) % m;
      if (dx < 0 || dx >= n || !vis[dx][dy]) continue;
      int u = getfather((((dx + 1) - 1) * m + (dy + 1)));
      fa[u] = (((x)-1) * m + (y));
    }
    seg[(((x)-1) * m + (y))] = {left, right};
  }
  printf("%d\n", ans);
  return 0;
}
