procedure crossover(var s, t, result: array of char);
begin
    (* insert your code here *)
end;


const
    MAXL = 100000;
var
    s, t  : array[0..MAXL] of char;
    r     : array[0..2*MAXL] of char;
    fr, fw: text;

begin
    assign(fr, 'input.txt');
    assign(fw, 'output.txt');
    reset(fr);
    rewrite(fw);
    readln(fr, s);
    readln(fr, t);

    crossover(s, t, r);
    writeln(fw, r);
    close(fr);
    close(fw);
end.