program cifra;
var f,g:text;
        v:array[0..101] of byte;



procedure read_solve;
var i,ln,lc,plc,nr,uc,t,c2:longint;
        c:char;
begin
        fillchar(v,sizeof(v),0);
        assign(f,'cifra.in');
        reset(f);
        assign(g,'cifra.out');
        rewrite(g);
        readln(f,t);
        for i:=1 to t do
                begin
                        ln:=0;
                        while not eoln(f) do
                                begin
                                        inc(ln);
                                        read(f,c);
                                        v[ln]:=ord(c)-ord('0');
                                end;
                        readln(f);
                        lc:=v[ln];
                        uc:=0;
                        if v[ln-1] mod 2=0 then
                                plc:=0 else plc:=1;
                        c2:=v[ln-1] div 2;
                        nr:=plc*10+lc;
                        case nr of
                                0:uc:=0;
                                1:uc:=1;
                                2:uc:=5;
                                3:uc:=2;
                                4:uc:=8;
                                5:uc:=3;
                                6:uc:=9;
                                7:uc:=2;
                                8:uc:=8;
                                9:uc:=7;
                                10:uc:=7;
                                11:uc:=8;
                                12:uc:=4;
                                13:uc:=7;
                                14:uc:=3;
                                15:uc:=8;
                                16:uc:=4;
                                17:uc:=1;
                                18:uc:=5;
                                19:uc:=4;
                                20:uc:=4;
                        end;
                        case c2 of
                                0:uc:=uc+0;
                                1:uc:=uc+4;
                                2:uc:=uc+8;
                                3:uc:=uc+2;
                                4:uc:=uc+6;
                        end;
                        writeln(g,uc mod 10);
                end;
        close(g);
end;


begin
        read_solve;
end.