Compilare: user.c: In function ‘main’: user.c:4:9: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("magicnum.in","r",stdin),freopen("magicnum.out","w",stdout),scanf("%d%d",&x,&y); ^ user.c:4:42: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("magicnum.in","r",stdin),freopen("magicnum.out","w",stdout),scanf("%d%d",&x,&y); ^ user.c:4:75: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] freopen("magicnum.in","r",stdin),freopen("magicnum.out","w",stdout),scanf("%d%d",&x,&y); ^