Compilare: user.cpp: In constructor ‘node::node()’: user.cpp:13:48: warning: passing NULL to non-pointer argument 2 of ‘void* memset(void*, int, size_t)’ [-Wconversion-null] memset(children, NULL, sizeof(children)); ^ user.cpp: In function ‘void insert(node*, char*)’: user.cpp:23:28: warning: NULL used in arithmetic [-Wpointer-arith] if(*s == '\n' || *s == NULL) ^ user.cpp: In function ‘void remove(node*, char*)’: user.cpp:40:28: warning: NULL used in arithmetic [-Wpointer-arith] if(*s == '\n' || *s == NULL) ^ user.cpp: In function ‘int count(node*, char*)’: user.cpp:52:28: warning: NULL used in arithmetic [-Wpointer-arith] if(*s == '\n' || *s == NULL) ^ user.cpp: In function ‘int prefix(node*, char*)’: user.cpp:66:28: warning: NULL used in arithmetic [-Wpointer-arith] if(*s == '\n' || *s == NULL) ^ user.cpp: In function ‘void solve(node*)’: user.cpp:79:10: warning: unused variable ‘g’ [-Wunused-variable] FILE*g = freopen("trie.out", "w", stdout); ^ user.cpp:81:9: warning: unused variable ‘cnt’ [-Wunused-variable] int cnt = 0; ^ user.cpp:84:26: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(p, Nmax, f); ^