Compilare: main.cpp: In function 'bool hopcroft(int)': main.cpp:15:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 15 | for(int i=0;i<v[k].size();i++) | ~^~~~~~~~~~~~ main.cpp:22:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 22 | for(int i=0;i<v[k].size();i++) | ~^~~~~~~~~~~~