Compilare: user.cpp: In function ‘int main()’: user.cpp:209:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1;i<P.size();i++) ^ user.cpp:223:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i;i<P.size()-1;i++) ^ user.cpp:223:16: warning: ‘i’ is used uninitialized in this function [-Wuninitialized] for(int i;i<P.size()-1;i++) ^