Compilare: user.c: In function ‘main’: user.c:52:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("ahocorasick.in","r",stdin),freopen("ahocorasick.out","w",stdout),scanf("%s",tx),scanf("%d",&n),t=V(); ^ user.c:52:48: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("ahocorasick.in","r",stdin),freopen("ahocorasick.out","w",stdout),scanf("%s",tx),scanf("%d",&n),t=V(); ^ user.c:52:84: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] freopen("ahocorasick.in","r",stdin),freopen("ahocorasick.out","w",stdout),scanf("%s",tx),scanf("%d",&n),t=V(); ^ user.c:52:99: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] freopen("ahocorasick.in","r",stdin),freopen("ahocorasick.out","w",stdout),scanf("%s",tx),scanf("%d",&n),t=V(); ^ user.c:54:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s",c),ins(t,c,i); ^