program lol;

var
    sogl: set of char = ['k','p','s','t','f','h'];{,'ц','ч','ш','щ'];}
    prev: set of char;
    curr: set of char;
    ans: set of char;
    c: char;
    s: string;
    i: integer;
    j: integer;

begin
    readln(s);
    prev := [];
    ans := [];

    for i := 1 to length(s) do
    begin
        if (s[i] = ',') or (s[i] = '.') then
        begin
            j := i - 1;
            curr := [];
            while (j >= 1) and (s[j] <> ',') do
            begin
                if not(s[j] in curr) then
                begin
                    if (s[j] in sogl) and (s[j] in prev) then
                        include (ans, s[j]);
                    include(prev, s[j]);
                    include(curr, s[j]);
                end;
                j := j - 1;
            end;
        end;
    end;

    for c := #0 to #255 do
        if c in ans then
            writeln(c);
end.