Compilare: main.cpp: In member function 'void DSUQ::qUndo()': main.cpp:64:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<DSUQ::update>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 64 | for(int i=0;i<upds.size();++i) undo(); | ~^~~~~~~~~~~~ main.cpp:66:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<DSUQ::update>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 66 | for(int i=0;i<upds.size();++i) join(upds[i].a, upds[i].b), upds[i].type=1; | ~^~~~~~~~~~~~