#define PB push_back
int N,M,A[1d5+1],I[1d5]={},ans[1d5],q=0;
VI E[1d5],V,Q;

{
	rd(N,M,A(N)--);
	rep(i,N-2) if(A[i]==A[i+2]) wt("No"),exit(0);
	rep(i,N-1){
		if(i%2) E[A[i+1]].PB(A[i]),I[A[i]]++;
		else E[A[i]].PB(A[i+1]),I[A[i+1]]++;
	}
	rep(i,M) if(I[i]==0) Q.PB(i);
	while(q<Q.size()){
		int p=Q[q++];
		V.PB(p);
		for(int e:E[p]) if(0==--I[e]) Q.PB(e);
	}
	if(V.size()!=M) wt("No"),exit(0);
	wt("Yes");
	rep(i,M) ans[V[i]]=i+1;
	wt(ans(M));
}