Compilare: main.cpp: In member function 'void TrieNode::insert(const string&, int)': main.cpp:23:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (index == s.size()) ~~~~~~^~~~~~~~~~~ main.cpp: In member function 'bool TrieNode::remove(const string&, int)': main.cpp:38:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (index == s.size()) ~~~~~~^~~~~~~~~~~ main.cpp: In member function 'int TrieNode::count(const string&, int)': main.cpp:58:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (index == s.size()) ~~~~~~^~~~~~~~~~~ main.cpp: In member function 'int TrieNode::prefix(const string&, int)': main.cpp:69:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (index == s.size()) ~~~~~~^~~~~~~~~~~ main.cpp: In member function 'bool TrieNode::remove(const string&, int)': main.cpp:54:5: warning: control reaches end of non-void function [-Wreturn-type] } ^