def henkan(S):
    S = list(S)
    cnvS_lists = [[S, []]]
    while len(cnvS_lists[0][0]) > 1:
        p_lists = []
        for i in range(len(cnvS_lists)):
            bef_S1 = cnvS_lists[i][0]
            cnv_S1 = cnvS_lists[i][1]
            cnv_S2_1 = cnv_S1 + [bef_S1[0]]
            cnv_S2_2 = cnv_S1 + [bef_S1[-1]]
            bef_S2_1 = bef_S1[1:]
            bef_S2_2 = bef_S1[:-1]
            p_lists.append([bef_S2_1, cnv_S2_1])
            p_lists.append([bef_S2_2, cnv_S2_2])
        cnvS_lists = p_lists
    for j in range(len(cnvS_lists)):
        if cnvS_lists[j] == [0]:
            continue
        for k in range(j + 1, len(cnvS_lists)):
            if cnvS_lists[j] == cnvS_lists[k]:
                cnvS_lists[k] = [0]
    zero_cnt = cnvS_lists.count([0])
    result = len(cnvS_lists) - zero_cnt
    return result

def main():
    S = input()
    print(henkan(S))

if __name__ == '__main__':
    main()