Compilare: user.cpp: In constructor ‘trie::trie()’: user.cpp:18:12: warning: converting to non-pointer type ‘int’ from NULL [-Wconversion-null] id = NULL; ^ user.cpp: In function ‘void update_trie(trie*, char*, int, int)’: user.cpp:31:14: warning: NULL used in arithmetic [-Wpointer-arith] if(*s == NULL) ^ user.cpp:47:22: warning: NULL used in arithmetic [-Wpointer-arith] if(node -> id == NULL) ^ user.cpp:59:61: warning: NULL used in arithmetic [-Wpointer-arith] if(pwr[newId] == pwr[node -> id] && *(s + 1) != NULL && ut[node -> id][poz + 1] != NULL && *(s + 1) < ut[node -> id][poz + 1]) ^ user.cpp:59:96: warning: NULL used in arithmetic [-Wpointer-arith] if(pwr[newId] == pwr[node -> id] && *(s + 1) != NULL && ut[node -> id][poz + 1] != NULL && *(s + 1) < ut[node -> id][poz + 1]) ^ user.cpp:69:61: warning: NULL used in arithmetic [-Wpointer-arith] if(pwr[newId] == pwr[node -> id] && *(s + 1) != NULL && ut[node -> id][poz + 1] != NULL && *(s + 1) > ut[node -> id][poz + 1]) ^ user.cpp:69:96: warning: NULL used in arithmetic [-Wpointer-arith] if(pwr[newId] == pwr[node -> id] && *(s + 1) != NULL && ut[node -> id][poz + 1] != NULL && *(s + 1) > ut[node -> id][poz + 1]) ^ user.cpp:84:26: warning: NULL used in arithmetic [-Wpointer-arith] if(node -> id == NULL) ^ user.cpp: In function ‘void query_trie(trie*, char*)’: user.cpp:93:14: warning: NULL used in arithmetic [-Wpointer-arith] if(*s == NULL) ^ user.cpp:98:20: warning: NULL used in arithmetic [-Wpointer-arith] if(*(s + 1) == NULL) ^ user.cpp: In function ‘int main()’: user.cpp:135:17: warning: unused variable ‘showId’ [-Wunused-variable] int showId = id[ut[i]]; ^ user.cpp:155:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < strlen(ut[sol]); i++) ^