d = {'A' : [1, 2], 'B' : [1, 3], 'C' : [1, 4], 'D' : [1, 5], 'E' : [1, 6], 'F' : [1, 7]}
n = input()
ans = [0] * 8
for c in n:
    ans[d[c][0]] += 1
    ans[d[c][1]] += 1
m = max(ans)
res = []
for i, x in enumerate(ans):
    if x == m:
        res.append(i)
print(*res)