Compilare: main.c: In function 'main': main.c:7:5: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("radixsort.in","r",stdin),freopen("radixsort.out","w",stdout),scanf("%d%lld%lld%lld",&n,&a,&b,&c); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:7:39: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("radixsort.in","r",stdin),freopen("radixsort.out","w",stdout),scanf("%d%lld%lld%lld",&n,&a,&b,&c); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:7:75: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] freopen("radixsort.in","r",stdin),freopen("radixsort.out","w",stdout),scanf("%d%lld%lld%lld",&n,&a,&b,&c); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~