citymapping.cpp: In function 'void find_roads(int, int, int*, int*, int*)':
citymapping.cpp:27:8: warning: statement has no effect [-Wunused-value]
27 | p[i] == i;
| ~~~~~^~~~
citymapping.cpp:48:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, std::pair<int, int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
48 | for (int i = 0; i < e.size(); i++) {
| ~~^~~~~~~~~~
/usr/bin/ld: /tmp/ccphtm7q.o: in function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccgbWPep.o:citymapping.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status