program sie;
var
  map:array[0..201,0..201]of longint;
  a,b,c,i,j,n,k:longint;
  F:BOOLEAN;
begin
  assign(input,'sie.in');
  assign(output,'sie.out');
  reset(input);
  rewrite(output);
  for i:=0 to 201 do begin
    for j:=0 to 201 do  map[i,j]:=-1;
  end;
  readln(n);
  for i:=1 to n do begin
     for j:=1 to n do begin
       read(a);
       map[i,j]:=a;
     end;
     readln;
  end;
  for i:=1 to n do begin
    for j:=i+1 to n do begin
      k:=1; f:=true;
      while (f) and(k<=n)do begin
        if (map[i,j]=map[i,k]+map[k,j])and(k<>i)and(k<>j) then f:=false
        else inc(k);
      end;
      if (f) and (k=n+1) then writeln(i,' ',j);
    end;
  end;
  close(input); close(output);
End.