Compilare: user.cpp: In function ‘int main()’: user.cpp:14:17: warning: unused variable ‘k’ [-Wunused-variable] int n,i,c1,c2,x,k,q; ^ user.cpp:14:19: warning: unused variable ‘q’ [-Wunused-variable] int n,i,c1,c2,x,k,q; ^ user.cpp:12:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] {freopen ("heavymetal.in","r",stdin); ^ user.cpp:13:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("heavymetal.out","w",stdout); ^ user.cpp:15:15: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:17:35: 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); ^