Compilare: user.cpp: In function ‘int main()’: user.cpp:28:19: warning: unused variable ‘pos’ [-Wunused-variable] int n,m,p,i,j,pos,pc,mc,nr,k,z; ^ user.cpp:28:23: warning: unused variable ‘pc’ [-Wunused-variable] int n,m,p,i,j,pos,pc,mc,nr,k,z; ^ user.cpp:28:26: warning: unused variable ‘mc’ [-Wunused-variable] int n,m,p,i,j,pos,pc,mc,nr,k,z; ^ user.cpp:29:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("colaj.in","r",stdin); ^ user.cpp:30:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("colaj.out","w",stdout); ^ user.cpp:31:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&n,&m,&p); ^ user.cpp:34:58: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&v[i].a,&v[i].b,&v[i].c,&v[i].d); ^