Compilare: user.c: In function ‘main’: user.c:81:13: warning: implicit declaration of function ‘qsort’ [-Wimplicit-function-declaration] qsort(c[i],C[i],sizeof(int),cmp); ^ user.c:51:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("cifrul.in","r",stdin); ^ user.c:52:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("cifrul.out","w",stdout); ^ user.c:54:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i",&t); ^ user.c:57:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i%i%i%i",&n,&m,&k,&d); ^ user.c:59:32: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] fr(i,0,m)fr(j,0,n)scanf("%i",a[i]+j); ^