After updating xcode13, we found that the brackets and other symbols in the project are gone after running the project, and the project style is different from that of the previous OC language. Please answer the question. Thank you

What is the specific method of skadnetwork advertising signature? Sign the Combined String Sign the combined UTF-8 string with the following key and algorithm: Your PKCS#8 private key. The Elliptic Curve Digital Signature Algorithm (ECDSA) with a SHA-256 hash. The resulting Digital Encoding Rules (DER)-formatted binary value is the signature. Can anyone provide a specific method? thank you

Sign the Combined String Sign the combined UTF-8 string with the following key and algorithm: Your PKCS#8 private key. The Elliptic Curve Digital Signature Algorithm (ECDSA) with a SHA-256 hash. The resulting Digital Encoding Rules (DER)-formatted binary value is the signature. Can you provide a more detailed description of how to generate a signature？Thank you in advance。