uses crt;

var S : array [1 .. 100] of string;

i, N, d, k, j : integer; X : string;

begin

clrscr;

writeln('Input'); readln(N);

for i := 1 to N do readln(S[i]);

writeln('Output');

for j := 1 to N do begin X := S[j];

for i := 1 to length(X) do

begin d := 0;

for k := 1 to length(X) do

if (i <> k) and (X[i] = X[k]) then

d := 1; if d = 0 then write(X[i]); end; end;

readln

end.

uses crt;
var
    s: ansistring;
    count_arr: array[char] of longint;
    i, t: longint;

function solve(s: ansistring): char;
var c: char;
begin
    fillchar(count_arr, sizeof (count_arr), 0);
    for c in s do inc(count_arr[c]);
    for c in char do
        if count_arr[c] = 1 then exit(c);
    exit();
end;

begin
    clrscr;
    readln(t);
    while t > 0 do 
        begin
            dec(t);
            readln(s);
            write(solve(s));
        end;
readln;
end.