Compilare: user.cpp: In function ‘int main()’: user.cpp:34:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j; ^ user.cpp:32:49: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("infasuratoareconvexa.in","r",stdin); ^ user.cpp:33:51: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("infasuratoareconvexa.out","w",stdout); ^ user.cpp:35:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:37:48: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lf%lf",&punct[i].x,&punct[i].y); ^