stations.cpp: In function 'std::vector<int> label(int, int, std::vector<int>, std::vector<int>)':
stations.cpp:25:14: error: request for member 'push_back' in 'v.std::vector<int>::operator[](((std::vector<int>::size_type)x))', which is of non-class type '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'}
25 | v[x].push_back(y);
| ^~~~~~~~~
stations.cpp:26:14: error: request for member 'push_back' in 'v.std::vector<int>::operator[](((std::vector<int>::size_type)y))', which is of non-class type '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'}
26 | v[y].push_back(x);
| ^~~~~~~~~
stations.cpp:30:22: error: request for member 'size' in 'v.std::vector<int>::operator[](((std::vector<int>::size_type)i))', which is of non-class type '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'}
30 | if((int)v[i].size() < (int)v[st].size()){
| ^~~~
stations.cpp:30:42: error: request for member 'size' in 'v.std::vector<int>::operator[](((std::vector<int>::size_type)st))', which is of non-class type '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'}
30 | if((int)v[i].size() < (int)v[st].size()){
| ^~~~