type vector=array[1..20] of byte;
const v:vector=(1,4,7,6,5,6,3,6,9,0,1,6,3,6,5,6,7,4,9,0);
var n,s,t,i,x,j:longint;
er:integer;
w:string;
f,g:text;
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,w);
w:=copy(w,length(w)-1,2);
val(w,x,er);
s:=(x div 20)*4 mod 10;
for i:=1 to x mod 20 do
  s:=(s+v[i]) mod 10;
writeln(g,s);
end;
close(g);
end.