A: https://blog.nowcoder.net/n/584a2605ea4743bda44f46a3ae0e60d3 B: https://blog.nowcoder.net/n/4d3c77fd567540078b5de65ea01f9d0e D: https://blog.nowcoder.net/n/ab45979d0f4448cda5f8fc5b38bb5e73 E: https://blog.nowcoder.net/n/59a8480b4bbf4e69b1523bbaa07a0c7e