Compilare: user.cpp: In function ‘void add(char*, int, nod**)’: user.cpp:13: warning: NULL used in arithmetic user.cpp:18: warning: NULL used in arithmetic user.cpp: In function ‘void remove(char*, int, nod**)’: user.cpp:25: warning: NULL used in arithmetic user.cpp:28: warning: NULL used in arithmetic user.cpp: In function ‘int getAp(char*, int, nod*)’: user.cpp:34: warning: NULL used in arithmetic user.cpp:37: warning: NULL used in arithmetic user.cpp: In function ‘int getPref(char*, int, nod*, int)’: user.cpp:47: warning: NULL used in arithmetic user.cpp: In function ‘int main()’: user.cpp:62: warning: format ‘%s’ expects type ‘char*’, but argument 3 has type ‘char (*)[22]’ user.cpp:53: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:54: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:62: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘int getPref(char*, int, nod*, int)’: user.cpp:49: warning: control reaches end of non-void function user.cpp: In function ‘int getAp(char*, int, nod*)’: user.cpp:39: warning: control reaches end of non-void function