Program cifra;
var i,n,t,j,k,p,s,ro:longint;
    x:string;
    f,q:text;
begin;
assign(f,'cifra.in');
reset(f);
assign(q,'cifra.out');
rewrite(q);
readln(f,t);
for j:=1 to t do
begin
readln(f,x);
val(x,n,ro);
s:=0;
        for i:=1 to n do
        begin
        p:=1;
                for k:=1 to i do
                p:=(p mod 10)*i;
        s:=s+(p mod 10);
        end;
writeln(q,s mod 10);
end;
close(f);
close(q);
end.