Compilare: user.c: In function ‘main’: user.c:25:9: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("sarpe2.in","r",stdin),freopen("sarpe2.out","w",stdout),scanf("%d%d",&n,&m); ^ user.c:25:40: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("sarpe2.in","r",stdin),freopen("sarpe2.out","w",stdout),scanf("%d%d",&n,&m); ^ user.c:25:71: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] freopen("sarpe2.in","r",stdin),freopen("sarpe2.out","w",stdout),scanf("%d%d",&n,&m); ^ user.c:27:11: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",x+i),p[x[i]]=i; ^ user.c:30:11: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&a[i][j]),s[i][j]=-1; ^