Compilare: user.cpp: In function ‘int main()’: user.cpp:61:34: warning: unused variable ‘j’ [-Wunused-variable] int i , vf , x , y , V , t , j , sol = 0 , nod; ^ user.cpp:64:26: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(IN,"r",stdin); ^ user.cpp:65:28: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(OUT,"w",stdout); ^ user.cpp:67:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d%d" , &n , &m ); ^ user.cpp:70:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d" , &a[i] ); ^ user.cpp:75:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d" , &V ); ^ user.cpp:77:35: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d%d" , &x , &y ); ^ user.cpp:131:17: warning: ‘nod’ may be used uninitialized in this function [-Wmaybe-uninitialized] while(( nod/2)) ^