1010\u0031\u0030 (C99)\U000031\U000030 (C99)\x31\x30 (encoding-dependent)\061\060 (encoding-dependent)\u{31}\u{30} (C++23)\x{31}\x{30} (C++23, encoding-dependent)\o{061}\o{060} (C++23, encoding-dependent)\U00000031\U00000030\u0031\u0030\x31\x30 (encoding-dependent)\061\060 (encoding-dependent)\u0031\u0030\u{31}\u{30}\u0031\u0030\x31\x30\31\30\000031\000030=31=30%31%30