Compilare: user.cpp: In constructor ‘TrieNode::TrieNode()’: user.cpp:21:40: warning: passing NULL to non-pointer argument 2 of ‘void* memset(void*, int, size_t)’ [-Wconversion-null] memset(next, NULL, sizeof(next)); ^ user.cpp: In function ‘void TrieInsert(TrieNode*, char*)’: user.cpp:30:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0 ; i < strlen(s) ; i++) ^ user.cpp: In function ‘int TrieDelete(TrieNode*, char*)’: user.cpp:47:16: warning: NULL used in arithmetic [-Wpointer-arith] if ( *s == NULL) ^ user.cpp: In function ‘int TrieSearch(TrieNode*, char*)’: user.cpp:65:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0 ; i < strlen(s) ; i++) ^ user.cpp: In function ‘int TriePre(TrieNode*, char*)’: user.cpp:81:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0 ; i < strlen (s); i++ ) ^