import collections

target = 'KUROI'
S = input()

def solve(S):
    lst = preprocess(S)
    m = len(lst) // len(target)
    dp = collections.defaultdict(int)
    dp[0,0,0,0] = 0
    for c in lst:
        update_dp(dp, c, m)
    return max(dp.values())


def preprocess(S):
    candidates = target + '?'
    dic = {c: i for i, c in enumerate(candidates)}
    return [dic[c] for c in S if c in dic]


def update_dp(dp, c, m):
    dp_copy = {key: val for key, val in dp.items()}
    for (k0, k1, k2, k3), val in dp_copy.items():
        if (c == 0 or c == 5) and m > k0:
            new_key = (k0 + 1, k1, k2, k3)
            if (new_key not in dp_copy) or dp_copy[new_key] < val:
                dp[new_key] = val
        if (c == 1 or c == 5) and k0 > k1:
            new_key = (k0, k1 + 1, k2, k3)
            if (new_key not in dp_copy) or dp_copy[new_key] < val:
                dp[new_key] = val
        if (c == 2 or c == 5) and k1 > k2:
            new_key = (k0, k1, k2 + 1, k3)
            if (new_key not in dp_copy) or dp_copy[new_key] < val:
                dp[new_key] = val
        if (c == 3 or c == 5) and k2 > k3:
            new_key = (k0, k1, k2, k3 + 1)
            if (new_key not in dp_copy) or dp_copy[new_key] < val:
                dp[new_key] = val
        if (c == 4 or c == 5) and k3 > val:
            dp[k0, k1, k2, k3] += 1

print(solve(S))