Compilare: user.cpp: In function ‘int main()’: user.cpp:154: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:155: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:159: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:161: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result user.cpp:173: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result /tmp/cctyvEGC.o: In function `main': user.cpp:(.text+0x5a5): warning: the `gets' function is dangerous and should not be used.