var n,i,m,j,k:longint;
     s:string;
     err:integer;
function f(n:longint):longint;
        var i,k:longint;
          begin
          k:=1;
         for i:=1 to n do k:=k*n mod 10;
         f:=k;
         end;




      begin
      assign(input,'cifra.in'); reset(input);
      assign(output,'cifra.out'); rewrite(output);


readln(j);
for k:=1 to j do begin readln(s); s:=copy(s,length(s)-1,2);
val(s,n,err);
m:=0;
for i:=1 to n do m:=(m+f(i)) mod 10;
writeln(m); end;
close(input);
close(output);
end.