Compilare: user.cpp:17: warning: integer overflow in expression user.cpp: In function ‘void read()’: user.cpp:34: warning: comparison between signed and unsigned integer expressions user.cpp:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void write()’: user.cpp:59: warning: comparison between signed and unsigned integer expressions user.cpp:60: warning: integer overflow in expression user.cpp:58: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result