Compilare: user.c: In function ‘main’: user.c:31:9: warning: implicit declaration of function ‘qsort’ [-Wimplicit-function-declaration] qsort(b,n,sizeof(int),cmp); ^ user.c:20:11: warning: unused variable ‘c’ [-Wunused-variable] int t,c=0; ^ user.c:11:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("streetcrypto.in","r",stdin); ^ user.c:12:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("streetcrypto.out","w",stdout); ^ user.c:21:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i",&t); ^ user.c:24:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i",&n); ^ user.c:25:23: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] fr(i,0,n)scanf("%lli",a+i); ^