program cifra;

var nr : array[0..19] of byte;
    f,g : text;
    i,a,b,t,j,x : integer;
    s : string;

function cifra(x : integer) : integer;
var c : integer;
begin
    c := 4*(x div 20) mod 10;
    x := x mod 20;
    c := (c+nr[x]) mod 10;
    cifra := c;
end;

begin
    nr[0] := 0; nr[1] := 1; nr[2] := 5; nr[3] := 2; nr[4] := 8; nr[5] := 3; nr[6] := 9;
    nr[7] := 2; nr[8] := 8; nr[9] := 7; nr[10] := 7; nr[11] := 8; nr[12] := 4;
    nr[13] := 7; nr[14] := 3; nr[15] := 8; nr[16] := 4; nr[17] := 1;
    nr[18] := 5; nr[19] := 4;

    assign(f,'cifra.in'); reset(f);
    assign(g,'cifra.out'); rewrite(g);

    readln(f,t);

    for i := 1 to t do begin
        readln(f,s); j := length(s);

        s := copy(s,j-1,2);
        val(s,x,j);
        writeln(g,cifra(x));
        end;

    close(f); close(g);

end.