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<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
const int N = 3002 * 6002;
int f[N];
int n, m;
int c[3], a[3][10];
const int dx[9] = {-1, -1, -1, 1, 1, 1, 0, 0};
const int dy[9] = {-1, 0, 1, -1, 0, 1, -1, 1};
int X;
int vis[N];
int find(int k)
{
    return f[k] == k ? k : f[k] = find(f[k]);
}
int hash(int x, int y)
{
    return (x-1)*m*2 + y;
}
void solve(int x, int y,int k)
{
    X++;
    c[k] = 0;
    vis[hash(x, y)] = X;
    for(int i = 0; i < 8; i++)
    {
        int tx = x + dx[i];
        int ty = y + dy[i];
        if(tx > n || tx <= 0)
            continue;
        if(ty > 2*m)
            ty = 1;
        if(ty <= 0)
            ty = 2*m;
        int id = hash(tx, ty);
        if(f[id] > 0 && vis[find(id)] != X)
        {
            vis[f[id]] = X;
            a[k][++c[k]] = find(id);
        }
    }
    return ;
}
int main()
{
    int p;
    scanf("%d%d%d", &n, &m, &p);
    int ans = 0;
    for(int i = 1; i <= p; i++)
    {
        int x, y;
        bool ok = true;
        scanf("%d%d", &x, &y);
        solve(x, y, 1);
        solve(x, y+m, 2);
        X++;
        for(int j = 1; j <= c[1]; j++)
            vis[a[1][j]] = X;
        for(int j = 1; j <= c[2]; j++)
            if(vis[a[2][j]] == X)
                ok = false;
        if(ok)
        {
            ans++;
            int q = hash(x, y);
            f[q] = q;
            for(int j = 1; j <= c[1]; j++)
                f[find(a[1][j])] = q;
            q += m;
            f[q] = q;
            for(int j = 1; j <= c[2]; j++)
                f[find(a[2][j])] = q;
        }
    }
    printf("%d\n", ans);
    return 0;
}

