Eroare de compilare: user.c:2:17: error: mem.h: No such file or directory user.c: In function 'main': user.c:62: warning: pointer targets in passing argument 1 of 'fgets' differ in signedness user.c:68: warning: implicit declaration of function 'memset' user.c:68: warning: incompatible implicit declaration of built-in function 'memset' user.c:70: warning: pointer targets in passing argument 1 of 'fgets' differ in signedness