program cifra;
var
j,i,t:integer;
f,g:text;
s,n:longint;
function putere(i:integer):longint;
var
j,d:integer;
begin
d:=1;
for j:=1 to n do d:=d*i;
putere:=d;
end;

begin
assign (f,'cifra.in'); reset (f);
assign (g,'cifra.out'); rewrite(g);
readln (f,t);
for j:=1 to t do begin;
    s:=0;
    readln (f,n);
    for i:=1 to n do
        s:=s+putere(i);
    writeln (g, s mod 10);
end;
close (f);
close (g);
end.