[C + +] there is an error in compiling C program under Linux’s Ubuntu: the solution of “strain ‘\ \ 302’ or ‘\ \ 240’ in program”

Reference article:

(1) [C + +] there is an error in compiling C program under Linux’s Ubuntu: the solution of “strain ‘\ \ 302’ or ‘\ \ 240’ in program”

（2） https://www.cnblogs.com/johnnyzen/p/7995666.html

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