Compilare: user.cpp: In function ‘void add_best_edge(std::vector<long long int>&, std::vector<long long int>&)’: user.cpp:48:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (pos + 1 < B.size()) { ^ user.cpp:59:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (pos + 1 < A.size()) { ^ user.cpp: In function ‘int main()’: user.cpp:98:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 1; i < street.size(); i++) ^ user.cpp:74:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("campanie.in","r",stdin); ^ user.cpp:75:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("campanie.out","w",stdout); ^ user.cpp:77:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &cities); ^ user.cpp:80:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:82:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld", &x); ^ user.cpp:88:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &k); ^ user.cpp:92:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld", &aux[j]); ^ user.cpp: In member function ‘void Airport::read()’: user.cpp:24:54: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld%lld%lld%lld", &x1, &y1, &x2, &y2); ^