Compilare: user.cpp: In function ‘int main()’: user.cpp:11:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("radixsort.in","r",stdin); ^ user.cpp:12:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("radixsort.out","w",stdout); ^ user.cpp:13:49: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(scanf("%d%d%d%d",&n,&a,&b,&c),v[1]=b,i=2;i<=n;v[i]=(1LL*a*v[i-1]+b)%c,++i); ^