program cifra;
type vector=array[1..100] of integer;
var v:vector;
    n:string;
    er,nr,i,t:integer;
    s:longint;
    f,g:text;
function putere(x:integer):longint;
var p,j:longint;
begin
p:=1;
for j:=1 to x do p:=(p*x)mod 10;
putere:=p;
end;
procedure formare (var v:vector);
var j,pr:integer;
begin
for j:=1 to 100 do begin
                   pr:=putere(j);
                   s:=(s+pr)mod 10;
                   v[j]:=s;
                   end;
end;
begin
s:=0;
assign(f,'cifra.in');reset(f);
assign(g,'cifra.out');rewrite(g);
readln(f,t);
for i:=1 to t do begin
                 readln(f,n);
                 if length(n)>3 then
                 delete(n,1,length(n)-2);
                 val(n,nr,er);
                 end;
write(g,v[nr]);
close(f);close(g);
end.