s = list(input().strip())
n = len(s)
used = [False] * n
count = 0

while True:
    pos = []
    current_pos = -1
    for target in 'KUROI':
        found = False
        for i in range(current_pos + 1, n):
            if not used[i] and (s[i] == target or s[i] == '?'):
                if s[i] == '?':
                    s[i] = target  # Replace '?' with the target character
                used[i] = True
                pos.append(i)
                current_pos = i
                found = True
                break
        if not found:
            break
    if len(pos) == 5:
        count += 1
    else:
        break

print(count)