Compilare: user.cpp: In function ‘int main()’: user.cpp:38:21: warning: NULL used in arithmetic [-Wpointer-arith] if(*it!=NULL) ^ user.cpp:45:21: warning: NULL used in arithmetic [-Wpointer-arith] if(*it!=NULL) ^ user.cpp:63:21: warning: NULL used in arithmetic [-Wpointer-arith] if(*it!=NULL&&*it<y) ^ user.cpp:70:21: warning: NULL used in arithmetic [-Wpointer-arith] if(*it!=NULL&&*it>y) ^ user.cpp:16:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pachete.in","r",stdin); ^ user.cpp:17:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pachete.out","w",stdout); ^ user.cpp:18:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&n,&x,&y); ^ user.cpp:20:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&v[i].x,&v[i].y); ^