Compilare: user.cpp: In function ‘void read()’: user.cpp:15:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j; ^ user.cpp:17:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d%d",&n,&m,&u); ^ user.cpp:19:45: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d",&umb[i].fs,&umb[i].sc); ^ user.cpp: In function ‘void solve()’: user.cpp:36:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d",&p); ^ user.cpp:39:43: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d%d%d",&lx,&ly,&rx,&ry); ^ user.cpp: In function ‘void query()’: user.cpp:68:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d",&p); ^ user.cpp:71:43: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d%d%d",&lx,&ly,&rx,&ry); ^ user.cpp: In function ‘int main()’: user.cpp:80:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("plaja.in","r",stdin); ^ user.cpp:81:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("plaja.out","w",stdout); ^