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 <algorithm>
using namespace std;
const int N = 3000+5;
int dx[10]={1,1, 1,-1,-1,-1,0, 0};
int dy[10]={0,1,-1, 0, 1,-1,1,-1};
int res, pr, n, m, T, i, te, k, nx, ny, ar;
int x, y;
struct coord
{
    int x, y;
};
coord p[N*2*N];
bool cmp(const int &a, const int &b)
{
    return (p[a].y < p[b].y);
}
int t1;
coord ara[100];
bool mark[N*2*N];
int ta, a[100];
int tb, b[100];
int get(int x)
{
    if(p[x].x==0)
    return 0;
    if(p[x].x==x)
    return x;
    return p[x].x = get(p[x].x);
}
int main()
{
    //freopen("input.txt", "r", stdin);
    scanf("%d%d%d", &n, &m, &T);
    for(te = 1; te <= T; ++ te)
    {
        scanf("%d%d", &x, &y);
//        x, y:x, y+m;
        ta = 0;tb = 0;
        for(k = 0; k < 8; ++ k)
        {
            nx = x+dx[k];
            ny = y+dy[k];
            if(nx >= 1 && nx <= n && ny >= 1 && ny <= 2*m)
            {
                ar = get(nx*(2*m)+ny);
                if(ar!=0)
                {
                if(ny < 1)
                ny = 2*m;
                if(ny > 2*m)
                ny = 1;
                    ++ ta;
                    a[ta] = ar;
                }
            }
        }
        for(k = 0; k < 8; ++ k)
        {
            nx = x+dx[k];
            ny = y+m+dy[k];
            if(nx >= 1 && nx <= n)
            {
                if(ny < 1)
                ny = 2*m;
                if(ny > 2*m)
                ny = 1;
                ar = get(nx*(2*m)+ny);
                if(ar!=0)
                {
                    ++ tb;
                    b[tb] = ar;
                }
            }
        }
        for(i = 1; i <= ta; ++ i)
        {
            mark[ a[i] ] = 1;
        }
        for(i = 1; i <= tb; ++ i)
        {
            if(mark[ b[i] ])
            goto x;
        }
        ++res;

        p[x*(2*m)+y].x = x*(2*m)+y;
        p[x*(2*m)+y].y = 1;
        a[0] = x*(2*m)+y;
        sort(a, a+ta+1, cmp);
        for(i = 0; i < ta; ++ i)
        {
            p[ a[i] ].x = a[ta];
            p[ a[ta] ].y+=p[ a[i] ].y;
        }
        p[x*(2*m)+y+m].x = x*(2*m)+y+m;
        p[x*(2*m)+y+m].y = 1;
        b[0] = x*(2*m)+y+m;
        sort(b, b+tb+1, cmp);
        for(i = 0; i < tb; ++ i)
        {
            p[ b[i] ].x = b[tb];
            p[ b[tb] ].y+=p[ b[i] ].y;
        }
        x:
        //
        for(i = 1; i <= ta; ++ i)
        {
            mark[ a[i] ] = 0;
        }
    }
    if(m==1)
    res = 0;
    printf("%d\n", res);
    return 0;
}
