Compilare: user.cpp: In function ‘int main()’: user.cpp:27:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("inversari.in","r",stdin); ^ user.cpp:28:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("inversari.out","w",stdout); ^ user.cpp:32:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&N,&M); ^ user.cpp:33:46: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(i = 1; i <= N; ++i) scanf("%d",&v[i]); ^ user.cpp:36:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&Q[i].x,&Q[i].y); ^