traffic.cpp: In member function 'int City::DFS(int)':
traffic.cpp:26:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, std::shared_ptr<City> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
26 | for (int j=0;j<roads.size();j++) {
| ~^~~~~~~~~~~~~
traffic.cpp: In member function 'int City::res()':
traffic.cpp:37:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, std::shared_ptr<City> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
37 | for (int i=0;i<roads.size();i++) {
| ~^~~~~~~~~~~~~
/tmp/ccY88ITn.o: In function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'
/tmp/ccqg4nI5.o:traffic.cpp:(.text.startup+0x0): first defined here
/tmp/ccY88ITn.o: In function `main':
grader.cpp:(.text.startup+0xd9): undefined reference to `LocateCentre(int, int*, int*, int*)'
collect2: error: ld returned 1 exit status