var i,a,j,n,p,m,t:longint;
    b,cod:integer;
    ba,bb:string;
    f,g:text;
begin
assign(f,'cifra.in');reset(f);
assign(g,'cifra.out');rewrite(g);
readln(f,t);
for i:=1 to t do begin
    readln(f,ba);
    if length(ba)>1 then
          bb:=ba[length(ba)-1]+ba[length(ba)]
    else bb:=ba[length(ba)];
    val(bb,b,cod);
  {  if (b div 10)mod 2=0 then n:=0
       else n:=5;}n:=0;
   for j:=1 to b do begin
        a:=j;
        m:=a mod 10;
        p:=a;
        if m=0 then n:=n+0;
        if m=1 then n:=n+1;
        if m=5 then n:=n+5;
        if m=6 then n:=n+6;
        if m=2 then begin
           if p mod 4=1 then n:=n+2;
           if p mod 4=2 then n:=n+4;
           if p mod 4=3 then n:=n+8;
           if p mod 4=0 then n:=n+6;
        end;
        if m=3 then begin
           if p mod 4=1 then n:=n+3;
           if p mod 4=2 then n:=n+9;
           if p mod 4=3 then n:=n+7;
           if p mod 4=0 then n:=n+1;
        end;
        if m=4 then begin
           if p mod 2=1 then n:=n+4;
           if p mod 2=0 then n:=n+6;
        end;
        if m=7 then begin
           if p mod 4=1 then n:=n+7;
           if p mod 4=2 then n:=n+9;
           if p mod 4=3 then n:=n+3;
           if p mod 4=0 then n:=n+1;
        end;
        if m=8 then begin
           if p mod 4=1 then n:=n+8;
           if p mod 4=2 then n:=n+4;
           if p mod 4=3 then n:=n+2;
           if p mod 4=0 then n:=n+6;
        end;
        if m=9 then begin
           if p mod 2=1 then n:=n+9;
           if p mod 2=0 then n:=n+1;
        end;

        n:=n mod 10;
    end;
    writeln(g,n);
end;
close(g);
end.