Compilare: user.cpp: In function ‘int main()’: user.cpp:149:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (ind != Events.size()) { ^ user.cpp:129:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("mm.in", "r", stdin); ^ user.cpp:130:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("mm.out", "w", stdout); ^ user.cpp:132:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &dim, &L, &n); ^ user.cpp:136:59: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d%d", &xx1, &yy1, &xx2, &yy2, &cost); ^