#include <fstream>
#define N 1001
using namespace std;
ifstream fin("camelot.in");
ofstream fout("camelot.out");
int a[N][N],x[N*N],y[100001],prim,ultim;
int dlin[8]={-2,-1,1,2,2,1,-1,-2};
int dcol[8]={1,2,2,1,-1,-2,-2,-1};
int xc,yc,cerinta,n,m,k,ni,nj,x1,y1;
int main()
{
    fin>>cerinta>>n>>m>>k;
    fin>>xc>>yc;
    prim=ultim=1;
    x[prim]=xc;
    y[prim]=yc;
    a[xc][yc]=1;
    while(prim<=ultim)
    {
        x1=x[prim];
        y1=y[prim];
        for(int t=0;t<8;t++)
        {
            ni=x1+dlin[t];
            nj=y1+dcol[t];
            if(ni>=1&&ni<=n&&nj>=1&&nj<=m&&a[ni][nj]==0)
            {
                ultim++;
                a[ni][nj]=a[x1][y1]+1;
                x[ultim]=ni;
                y[ultim]=nj;
            }
        }
        prim++;
    }
    int mini=N*N,maxi=0;
    for(int i=1;i<=k;i++)
    {
        fin>>x1>>y1;
        if(a[x1][y1]>maxi)
            maxi=a[x1][y1];
        if(a[x1][y1]<mini)
            mini=a[x1][y1];
    }
    if(cerinta==1)
        fout<<mini-1;
    else fout<<maxi-1;
    return 0;
}