Compilare: user.cpp: In function ‘int main()’: user.cpp:104:44: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("dreptunghiuri4.in","r",stdin); ^ user.cpp:105:46: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("dreptunghiuri4.out","w",stdout); ^ user.cpp:106:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &N,&K); ^ user.cpp:109:67: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &v[i].A.x,&v[i].A.y,&v[i].B.x,&v[i].B.y); ^