import java.io.*;
import java.util.*;

public class Solution {

    public static void main(String[] args) {
        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
        Scanner inp=new Scanner(System.in);
        int cost=0,wri=0,wci=0,ws=0,sum=0,i=0,j=0;
        int ms[][]=new int[3][3];
        for(i=0;i<3;i++){
            sum=0;
            for(j=0;j<3;j++){
                ms[i][j]=inp.nextInt();
                sum=sum+ms[i][j] ;
            }
            if(sum!=15){
                wri=i;
                ws=sum;
            }
        }
        for(i=0;i<3;i++){
            sum=0;
            for(j=0;j<3;j++){
                sum=sum+ms[j][i] ;
            }
            if(sum!=15){
                wci=i;
            }
        }
        cost=(int)Math.abs((15-(ws-(ms[wri][wci])))-ms[wri][wci]);
        System.out.println(cost) ;
        
        
        
        
          
    }
}