var f,g:text;
t,k,i,s,j:integer;
function putere(x,a:integer):integer;
var i,p:integer;
begin
p:=1;
for i:=1 to a do
p:=p*x;
putere:=p;
end;
begin
assign(f,'cifra.in');
reset(f);
readln(f,t);
assign(g,'cifra.out');
rewrite(g);
for i:=1 to t do
begin
s:=0;
readln(f,k);
for j:=1 to k do
s:=s+putere(j,j);
writeln(g,s mod 10);
end;
close(f);
close(g);
end.