Compilare: main.cpp: In function 'void add(node*, int)': main.cpp:27:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 27 | if (depth==s.size()) | ~~~~~^~~~~~~~~~ main.cpp: In function 'int nr_strings(node*, int)': main.cpp:46:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 46 | if (depth==s.size()) | ~~~~~^~~~~~~~~~ main.cpp: In function 'int longest_prefix(node*, int)': main.cpp:61:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 61 | if (depth==s.size()) | ~~~~~^~~~~~~~~~ main.cpp: In function 'bool del(node*, int)': main.cpp:76:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 76 | if (depth==s.size()) | ~~~~~^~~~~~~~~~