duplicate symbol OBJC_CLASS_Register1ViewController in:
/Users/nb/Library/Developer/Xcode/DerivedData/lottery-dysorfsvdnhspoaasloexqipojof/Build/Intermediates.noindex/lottery.build/Debug-iphoneos/lottery.build/Objects-normal/arm64/LoginViewController.o
/Users/nb/Library/Developer/Xcode/DerivedData/lottery-dysorfsvdnhspoaasloexqipojof/Build/Intermediates.noindex/lottery.build/Debug-iphoneos/lottery.build/Objects-normal/arm64/Register1ViewController.o
ld: 2 duplicate symbols for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
這種錯誤是import 了.m文件
Xcode中類文件后面的M,A,和敬?等符號,Xcode使用Git的符號表示的意思
https://blog.csdn.net/coco__d/article/details/52763861