Compilare: user.c:5:11: warning: conflicting types for built-in function ‘pow’ long long pow(long long a, int b) { ^~~ user.c: In function ‘main’: user.c:19:5: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("dirichlet.in","r",stdin); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ user.c:20:5: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("dirichlet.out","w",stdout); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ user.c:21:5: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^~~~~~~~~~~~~~