stations.cpp: In function 'void DFS(int)':
stations.cpp:12:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
12 | for (int i = 0; i < adj[v].size(); i++) {
| ~~^~~~~~~~~~~~~~~
stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:48:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
48 | for (int i = 0; i < c.size(); i++) {
| ~~^~~~~~~~~~
stations.cpp:56:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
56 | int l = c[i], r = ((i == c.size() - 1) ? s : c[i + 1]);
| ~~^~~~~~~~~~~~~~~
stations.cpp:61:1: warning: control reaches end of non-void function [-Wreturn-type]
61 | }
| ^