program p1;
var f,g:text;
    n,i,t,y,uc1,e,b,uc:longint;
begin
assign(f,'cifra.in');reset(f);
assign(g,'cifra.out');rewrite(g);
readln(f,n);
e:=0;
uc:=1;
for i:=1 to n do
begin
readln(f,t);
e:=e+1;
uc:=1;
for i:=1 to e
    do
    begin
    uc:=(uc*e)mod 10;
    end;
     uc1:=(uc1+uc)mod 10;
writeln(g,uc1);
end;
close(f);
close(g);
end.