N,M = map(int,input().split())
A = list(map(int,input().split()))
ALL = [i for i in range(M)]
ALL = set(ALL)
G = [[] for _ in range(M)]
for i in range(N-1):
    a = A[i] - 1 #0index
    b = A[i+1] - 1
    if a == b:
        print("No");exit()
    if i < N-2:
        c = A[i+2] - 1
        if a == c:
            print("No");exit()
    if i%2 == 0:
        G[a].append(b)
        ALL.discard(b)
    else:
        G[b].append(a)
        ALL.discard(a)
#print(G)

ALL = list(ALL)
used = set([])
TS = []
def dfs(v):
  if v in used:
    return
  used.add(v)
  for w in G[v]:
    if w in used:
      continue
    dfs(w)
    TS.append(w) #帰りがけで記録
for root in ALL: #すべての始点について
  dfs(root)
  TS.append(root)
TS.reverse() #最後に反転
#print(TS)

if len(TS) < M:
    print("No")
else:
    ans = [-1]*M
    for i, v in enumerate(TS):
        ans[v] = i + 1
    print("Yes")
    print(*ans)