Compilare: user.c: In function ‘main’: user.c:25:5: warning: passing argument 4 of ‘qsort’ from incompatible pointer type [enabled by default] qsort(v+1,N,4,comp); ^ In file included from user.c:2:0: /usr/include/stdlib.h:761:13: note: expected ‘__compar_fn_t’ but argument is of type ‘int (*)(void *, void *)’ extern void qsort (void *__base, size_t __nmemb, size_t __size, ^ user.c:19:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&N); ^ user.c:22:15: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",v+i); ^