Eroare de compilare: user.cpp: In function ‘void insert_trie(char*, int, node*)’: user.cpp:29: error: ‘strlen’ was not declared in this scope user.cpp:33: error: ‘strncpy’ was not declared in this scope user.cpp: In function ‘bool delete_trie(char*, int, node*)’: user.cpp:50: error: ‘strlen’ was not declared in this scope user.cpp: In function ‘int howmany(char*, int, node*)’: user.cpp:81: error: ‘strlen’ was not declared in this scope user.cpp: In function ‘int pref_len(char*, int, node*)’: user.cpp:97: error: ‘strlen’ was not declared in this scope