Compilare: user.cpp: In function ‘void add_word(trie*, char*)’: user.cpp:24:12: warning: NULL used in arithmetic [-Wpointer-arith] if(*s==NULL) ///Daca am ajuns la finalul cuvantului ^ user.cpp: In function ‘int find_word(trie*, char*)’: user.cpp:41:12: warning: NULL used in arithmetic [-Wpointer-arith] if(*s==NULL) ^ user.cpp: In function ‘void delete_word(trie*, char*)’: user.cpp:54:12: warning: NULL used in arithmetic [-Wpointer-arith] if(*s==NULL) ^ user.cpp: In function ‘int find_longest_prefix(trie*, char*)’: user.cpp:68:14: warning: NULL used in arithmetic [-Wpointer-arith] if(*s == NULL) ^ user.cpp: In function ‘int find_word(trie*, char*)’: user.cpp:50:1: warning: control reaches end of non-void function [-Wreturn-type] } ^