Compilare: user.cpp: In function ‘void read()’: user.cpp:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result user.cpp:17: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result user.cpp: In function ‘void write()’: user.cpp:77: warning: comparison between signed and unsigned integer expressions /tmp/ccA6xtQh.o: In function `read()': user.cpp:(.text+0x1cc): warning: the `gets' function is dangerous and should not be used.