def foata_bijection(elt):
    L = list(elt)
    M = []
    for e in L:
        M.append(e)
        k = len(M)
        if k <= 1:
            continue

        a = M[-2]
        M_prime = [0]*k
        if a > e:
            index_list = [-1] + [i for i in range(k - 1) if M[i] > e]
        else:
            index_list = [-1] + [i for i in range(k - 1) if M[i] < e]

        for j in range(1, len(index_list)):
            start = index_list[j-1] + 1
            end = index_list[j]
            M_prime[start] = M[end]
            for x in range(start + 1, end + 1):
                M_prime[x] = M[x-1]
        M_prime[k-1] = e
        M = M_prime
    return Permutations()(M)

def statistic(pi):
    l = 1
    pi_new = pi
    while True:
        pi_new = foata_bijection(pi_new)
        if pi_new == pi:
            return l
        l += 1