program cifra;
var f,g : text;
    p,s,t,i : byte;
    w : string[100];
    j,x,k : real;

function putere(nr : real) : byte;
begin
    p := 1; k := 1;
    while k <= nr do begin
        p := trunc(p*nr) mod 10;
        k := k + 1;
        end;
    putere := p;
end;

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,w); val(w,x,p);
        j := 1; s := 0;
        while j <= x do begin
            s := (s+putere(j)) mod 10;
            j := j + 1;
            end;
        writeln(g,s:0);
        end;
    close(f); close(g);
end.