mod = 1000000007
eps = 10**-9


def main():
    import sys
    input = sys.stdin.readline

    N, M = map(int, input().split())
    A = list(map(int, input().split()))

    for i in range(N-2):
        if A[i] == A[i+1] or A[i+1] == A[i+2] or A[i] == A[i+2]:
            print("No")
            exit()

    adj = [[] for _ in range(M+1)]
    in_num = [0] * (M+1)
    for i in range(N-1):
        u, v = A[i], A[i+1]
        if i & 1:
            adj[v].append(u)
            in_num[u] += 1
        else:
            adj[u].append(v)
            in_num[v] += 1
    st = []
    for v in range(1, M+1):
        if in_num[v] == 0:
            st.append(v)
    cnt = 0
    ans = [0] * M
    seen = [0] * (M+1)
    while st:
        v = st.pop()
        if seen[v]:
            continue
        else:
            seen[v] = 1
        cnt += 1
        ans[v-1] = cnt
        for u in adj[v]:
            in_num[u] -= 1
            if in_num[u] == 0:
                st.append(u)
    if cnt == M:
        print("Yes")
        print(*ans)
    else:
        print("No")


if __name__ == '__main__':
    main()