Compilare: user.cpp: In function ‘void trie_add(std::string)’: user.cpp:30:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<sir.size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:47:19: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses] cin>>n>>k>>sir+1; ^ user.cpp:56:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(cuv[i].size()<=lim) ^ user.cpp:63:44: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=2,k=0;j<=cuv[i].size();j++) ^ user.cpp:73:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(k==cuv[i].size()) ^