Compilare: main.cpp: In function 'void adaugare_cuvant(char*)': main.cpp:31:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<strlen(s);i++) ~^~~~~~~~~~ main.cpp: In function 'int nr_aparitii_cuvant(char*)': main.cpp:47:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<strlen(s);i++) ~^~~~~~~~~~ main.cpp: In function 'int cel_mai_lung_prefix(char*)': main.cpp:62:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<strlen(s);i++) ~^~~~~~~~~~ main.cpp: In function 'int stergere_cuvant(Trie*, char*)': main.cpp:75:12: warning: NULL used in arithmetic [-Wpointer-arith] if( *s == NULL) ^~~~