Compilare: main.c: In function 'fact0': main.c:12:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ main.c: In function 'main': main.c:16:2: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("fact.in","r",stdin); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:17:2: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("fact.out","w",stdout); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:20:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] scanf("%i",&p); ^~~~~~~~~~~~~~