int a[1d5],b[1d5],c[1d5];
{
	int@n;
	rd(a(n-1));
	rep(i,n-1)b[i]=i;
	sortA(n-1,a,b);
	rep(i,n-1){
		if(a[i]>i+1){
			wt("NO");
			exit(0);
		}
		c[b[i]]=i+1-a[i];
	}
	wt("YES");
	wtLn(c(n-1));
}