roads.cpp: In function 'void dfs(int, int)':
roads.cpp:28:37: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
28 | while (!tmp.empty()&&(tmp.size()>k||(tmp.back() < 0)))
| ~~~~~~~~~~^~
roads.cpp:34:39: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
34 | while (!tmp2.empty()&&(tmp2.size()>k+1||(tmp2.back()<0)))
| ~~~~~~~~~~~^~~~
roads.cpp: In function 'std::vector<long long int> minimum_closure_costs(int, std::vector<int>, std::vector<int>, std::vector<int>)':
roads.cpp:47:13: warning: unused variable 'u' [-Wunused-variable]
47 | int u=U[i]; int v=V[i];
| ^
roads.cpp:47:25: warning: unused variable 'v' [-Wunused-variable]
47 | int u=U[i]; int v=V[i];
| ^
roads.cpp:55:26: warning: comparison of integer expressions of different signedness: 'std::priority_queue<long long int, std::vector<long long int>, std::greater<long long int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
55 | while (pq.size() > k)
| ~~~~~~~~~~^~~