Compilare: user.cpp: In function ‘int main()’: user.cpp:49:15: warning: unused variable ‘b’ [-Wunused-variable] int i,j,k,b[Nmax],l1,l2; ^ user.cpp:50:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ksecv.in","r",stdin); ^ user.cpp:51:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ksecv.out","w",stdout); ^ user.cpp:52:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n,&k); ^ user.cpp:53:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(i=1;i<=n;++i) scanf("%d", &a[i]); ^