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 = 3e3 + 10, M = 2e6 + 10;
inline int read() {
  int x = 0, f = 0;
  char ch = getchar();
  while (!isdigit(ch)) f |= ch == '-', ch = getchar();
  while (isdigit(ch)) x = x * 10 + ch - '0', ch = getchar();
  return f ? -x : x;
}
const int way[8][2] = {{0, 1},   {0, -1}, {-1, 1}, {-1, 0},
                       {-1, -1}, {1, 1},  {1, 0},  {1, -1}};
int vis[N][N << 1], w[M], f[M], Vis[M], q[M];
inline int find(int u) { return f[u] == u ? u : f[u] = find(f[u]); }
inline void ins(int x, int y, int n, int m, int &res) {
  vis[x][y] = ++res, f[res] = res;
  for (int i = 0; i < 8; ++i) {
    int X = x + way[i][0], Y = y + way[i][1];
    if (Y == 0) Y = 2 * m;
    if (Y > 2 * m) Y = 1;
    if (vis[X][Y]) f[find(vis[X][Y])] = res;
  }
}
int main() {
  int n = read(), m = read(), Q = read(), res = 0;
  for (int cnt = 0; Q; --Q, ++cnt) {
    int x1 = read(), y1 = read(), w1 = 0;
    int x2 = x1, y2 = y1 + m, w2 = 0, flg = 0, l = 0;
    for (int i = 0; i < 8; ++i) {
      int X = x1 + way[i][0], Y = y1 + way[i][1];
      if (Y == 0) Y = 2 * m;
      if (Y > 2 * m) Y = 1;
      if (vis[X][Y]) Vis[find(vis[X][Y])] = 1, q[++l] = find(vis[X][Y]);
    }
    for (int i = 0; i < 8; ++i) {
      int X = x2 + way[i][0], Y = y2 + way[i][1];
      if (X < 1 || Y < 1 || X > n || Y > 2 * m) continue;
      if (vis[X][Y]) flg |= Vis[find(vis[X][Y])];
    }
    for (int i = 1; i <= l; ++i) Vis[q[i]] = 0;
    if (flg) {
      continue;
    }
    ins(x1, y1, n, m, res), ins(x2, y2, n, m, res);
  }
  printf("%d\n", m != 1 ? res >> 1 : 0);
  for (int i = 1; i <= res; ++i) f[i] = w[i] = 0;
  for (int i = 1; i <= n; ++i)
    for (int j = 1; j <= m * 2; ++j) vis[i][j] = 0;
  return 0;
}
