Compilare: user.cpp: In function ‘void cit()’: user.cpp:42: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:45: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:48: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void pre()’: user.cpp:56: warning: unused variable ‘n1’ user.cpp:56: warning: unused variable ‘n2’ user.cpp:56: warning: unused variable ‘lg’ user.cpp: In function ‘void afi()’: user.cpp:123: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:149: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:150: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result