Compilare: user.cpp: In function ‘void invx(std::vector<std::pair<int, int> >&)’: user.cpp:15:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v.size();++i) ^ user.cpp: In function ‘void invy(std::vector<std::pair<int, int> >&)’: user.cpp:21:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v.size();++i) ^ user.cpp: In function ‘std::pair<std::pair<int, int>, std::pair<int, int> > patr(std::vector<std::pair<int, int> >&)’: user.cpp:28:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v.size();++i) ^ user.cpp: In function ‘bool verif(std::vector<std::pair<int, int> >&, int)’: user.cpp:41:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v.size();++i) ^ user.cpp: In function ‘bool check(int)’: user.cpp:65:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<p.size();++i) ^