Compilare: user.cpp: In function ‘int main()’: user.cpp:20:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("alee.in","r",stdin); ^ user.cpp:21:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("alee.out","w",stdout); ^ user.cpp:23:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%hd%hd",&n,&m); ^ user.cpp:26:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%hd%hd",&b,&c); ^ user.cpp:40:46: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%hd%hd%d%d",&b,&c,&stop.x,&stop.y); ^