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>
using namespace std;
const int N = 3020;
const int dx[10] = {0, 0, 0, 1, -1, 1, 1, -1, -1},
          dy[10] = {0, 1, -1, 0, 0, 1, -1, 1, -1};
int n, m, q;
int fa[N * N * 2], vis[N][N * 2];
inline int getfa(int x) { return fa[x] == x ? x : fa[x] = getfa(fa[x]); }
inline int na(int x, int y) { return (x - 1) * m * 2 + y; }
inline bool __(int &x, int &y) {
  if (y == m * 2 + 1) y = 1;
  if (y == 0) y = 2 * m;
  if (x <= 0 || x >= n + 1 || !vis[x][y])
    return 1;
  else
    return 0;
}
inline bool pd(int x, int y) {
  for (int i = 1; i <= 8; i++) {
    int nx = x + dx[i], ny = y + dy[i];
    if (__(nx, ny)) continue;
    int s = na(nx, ny);
    for (int j = 1; j <= 8; j++) {
      int mx = x + dx[j], my = y + dy[j] + m;
      if (__(mx, my)) continue;
      int ns = na(mx, my);
      if (getfa(ns) == getfa(s)) return 1;
    }
  }
  return 0;
}
inline void _(int x, int y) {
  for (int i = 1; i <= 8; i++) {
    int nx = x + dx[i], ny = y + dy[i];
    if (__(nx, ny)) continue;
    int s = na(nx, ny);
    fa[getfa(s)] = getfa(na(x, y));
  }
  vis[x][y] = 1;
}
inline void work() {
  scanf("%d%d%d", &n, &m, &q);
  if (m == 1) {
    puts("0");
    return;
  }
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m * 2; j++) {
      fa[na(i, j)] = na(i, j);
    }
  }
  int ans = q;
  while (q--) {
    int x, y;
    scanf("%d%d", &x, &y);
    if (pd(x, y))
      ans--;
    else
      _(x, y), _(x, y + m);
  }
  printf("%d\n", ans);
}
int main() { work(); }
