Compilare: user.cpp: In function 'int main()': user.cpp:23: warning: comparison between signed and unsigned integer expressions user.cpp:30: warning: comparison between signed and unsigned integer expressions user.cpp:50: warning: comparison between signed and unsigned integer expressions user.cpp:52: warning: comparison between signed and unsigned integer expressions /tmp/ccaUEkTM.o: In function `main': user.cpp:(.text+0x56): warning: the `gets' function is dangerous and should not be used.