Compilare: main.cpp: In function 'void modif(nod*, std::__cxx11::string, int, int)': main.cpp:18:7: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i == s.size()) { ~~^~~~~~~~~~~ main.cpp: In function 'int apar(nod*, std::__cxx11::string, int)': main.cpp:31:7: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i == s.size()) { ~~^~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:50:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("trie.in", "r", stdin); ^ main.cpp:51:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("trie.out", "w", stdout); ^