Compilare: user.cpp: In function ‘int main()’: user.cpp:22:29: warning: variable ‘l’ set but not used [-Wunused-but-set-variable] int a,b,n,i,tempx,tempy,l,r,s; ^ user.cpp:20:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dunarea.in","r",stdin); ^ user.cpp:21:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dunarea.out","w",stdout); ^ user.cpp:23:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&a,&b,&n); ^ user.cpp:26:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&tempx,&tempy); ^