Compilare: user.c: In function ‘main’: user.c:6:19: warning: unused variable ‘r’ [-Wunused-variable] int n,k,a,b,i,r,sc,x; ^ user.c:8:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("divk.in","r",stdin); ^ user.c:9:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("divk.out","w",stdout); ^ user.c:10:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&n,&k,&a,&b); ^ user.c:14:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&x); ^