Compilare: user.cpp: In function ‘int main()’: user.cpp:13:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<=s.size()-1;i++) ^ user.cpp:14:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<prop.size();j++) ^ user.cpp:28:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<=s.size()-1;i++) ^ user.cpp:35:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<prop.size();j++) ^