#include<iostream>
using namespace std;
int main()
{
int marinecount,x=0,y=0,rows=0,columns=0,cover;
int marinepositions[36][2];
static int marky[8],markx[8];
cin>>marinecount;
for(int i=0;i<marinecount;i++)
{
        for(int j=0;j<2;j++)
        {
                cin>>marinepositions[i][j];
                }}
                
  for(int i = 0; i < marinecount;i++)
                {
                    x = marinepositions[i][0];
                    markx[x]++;
                   
                    y = marinepositions[i][1];
                    marky[y]++;
                }              
                

                        
                
                for(int i=0;i<8;i++)
                {
                        if(marky[i]!=0)
                        columns++;
                        if(markx[i]!=0)
                        rows++;
                        }
                       
                        cover=(columns*8)+(8-columns)*rows;
                        cout<<cover;
                        
                        return 0;
                        }