I goofed and failed to put a space after the "case" word: switch(nu){ case1: v1 =val;break; case2: v2 =val;break; case3: v3 =val;break; case4: v4 =val;break; }
gcc compiler showed NO errors or warnings. Execution of the code produced incorrect results. After I added a space(no other changes), everything compiled and ran perfectly. switch(nu){ case 1: v1 =val;break; case 2: v2 =val;break; case 3: v3 =val;break; case 4: v4 =val;break; } version info: Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/c++/4.2.1 Apple clang version 13.0.0 (clang-1300.0.29.30) Target: x86_64-apple-darwin20.6.0 Thread model: posix InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin Thanks, wl jackson Sent with [ProtonMail](https://protonmail.com/) secure email.