Compilare: main.cpp: In function 'int p1(int)': main.cpp:16:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<std::pair<int, int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 16 | for(int i=1;i<=connections.size();i++) | ~^~~~~~~~~~~~~~~~~~~~ main.cpp:28:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 28 | for(int i=0;i<connections[head].size();i++) | ~^~~~~~~~~~~~~~~~~~~~~~~~~