Compilare: user.cpp: In function ‘void ReadData()’: user.cpp:28:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d ", &n, &m); ^ user.cpp:30:57: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lf %lf ", &coord[i].first, &coord[i].second); ^ user.cpp:35:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d ", &x, &y); ^ user.cpp: In function ‘int main()’: user.cpp:148:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nowhere-zero.in", "r", stdin); ^ user.cpp:149:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nowhere-zero.out", "w", stdout); ^