var
    count1, count2:array [1..26] of char;
    s1, s2, s3:string;
    i:integer;
begin
    readln(s1);
    readln(s2);
    readln(s3);
    for i := 1 to length(s1) do
        inc(count1[ord(s1[i]) - 'A' + 1]);
    for i := 1 to length(s2) do
        inc(count1[ord(s2[i]) - 'A' + 1]);
    for i := 1 to length(s3) do
        inc(count2[ord(s3[i]) - 'A' + 1]);
    for i := 1 to 26 do
        if (count1[i] <> count2[i]) then
        begin
            writeln('NO');
            exit;
        end;
    writeln('YES');
end.