import sys
input = sys.stdin.readline

from collections import Counter

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

ANS=[]

for i in range(20):
    B=A+[i]

    C=Counter(B)
    L=list(C.values())
    L.sort()

    if L==[2,3,3,3,3]:
        ANS.append(i)

print(len(ANS))
print(*ANS)