var f,g:text;
    i,j,n:integer;
    a,min,s:longint;
begin
s:=0;
assign(f,'cc.in');reset(f);readln(f,n);
assign(g,'cc.out');rewrite(g);
for i:=1 to n do
begin
 min:=2000000000;
 for j:=1 to n do
  begin
  read(f,a);
  if min>a then min:=a;
  end;
 s:=s+min;
readln(f);
end;

write(g,s);
close(f);close(g);
end.