Compilare: user.cpp: In member function ‘void ism::read_array()’: user.cpp:42: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In member function ‘void ism::preprocess()’: user.cpp:64: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:102: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:103: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:106: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:112: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result