Compilare: user.cpp: In function ‘void dijkstra(int, int, std::vector<std::vector<edge> >&, std::vector<bool>&, std::vector<int>&)’: user.cpp:48:47: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < lists[v].size(); i++) { ^ user.cpp: In function ‘int main()’: user.cpp:72:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("algoritm.in", "r", stdin); ^ user.cpp:73:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("algoritm.out", "w", stdout); ^ user.cpp:76:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &T); ^ user.cpp:79:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &N, &M); ^ user.cpp:87:42: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &x, &y, &z); ^