Compilare: user.cpp: In function ‘int main()’: user.cpp:83:45: warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 3 has type ‘std::vector<Edge>::size_type {aka unsigned int}’ [-Wformat=] printf("%d\n%lu\n", min_cost, ama.size()); ^ user.cpp:36:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("apm.in", "r", stdin); ^ user.cpp:37:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("apm.out", "w", stdout); ^ user.cpp:39:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &N, &M); ^ user.cpp:48:42: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d%d", &n1, &n2, &cost); ^