#include<bits/stdc++.h>
using namespace std;
int main()
{
int n,m,k,x,y;
cin>>n>>m>>k;
int a[n][n];
memset(a,0,sizeof(a));
for(int i=2;i<=m+1;i++)
{
cin>>x>>y;
a[x][y]=1;
a[x-1][y]=1;
a[x-2][y]=1;
a[x][y-1]=1;
a[x][y-2]=1;
a[x][y+1]=1;
a[x][y+2]=1;
a[x-1][y]=1;
a[x-2][y]=1;
a[x-1][y-1]=1;
a[x+1][y-1]=1;
a[x-1][y+1]=1;
a[x+1][y+1]=1;
}
if(k>0)
{
for(int i=m+2;i<m+k+1;i++)
{
cin>>x>>y;
a[x][y]=1;
a[x-1][y]=1;
a[x-2][y]=1;
a[x][y-1]=1;
a[x][y-2]=1;
a[x][y+1]=1;
a[x][y+2]=1;
a[x-1][y]=1;
a[x-2][y]=1;
a[x+1][y-1]=1;
a[x+2][y-1]=1;
a[x+1][y-2]=1;
a[x+2][y-2]=1;
a[x+1][y+1]=1;
a[x+2][y+1]=1;
a[x+1][y+2]=1;
a[x+2][y+2]=1;
a[x-1][y-1]=1;
a[x-2][y-1]=1;
a[x-1][y-2]=1;
a[x-2][y-2]=1;
a[x-1][y+1]=1;
a[x-2][y+1]=1;
a[x-1][y+2]=1;
a[x-2][y+2]=1;
}
}
int qw=0;
for(int i=1;i<=n;i++)
{
for(int j=1;j<=n;j++)
{
if(a[i][j]==0)
qw+=1;
}
}
cout<<qw;
}