def main():
    import sys
    n, *rest = map(int, sys.stdin.read().split())
    a = rest[:n]
    sorted_a = sorted(a)
    if a == sorted_a:
        print(0)
        return

    # 找出目标数组的后缀是否正确
    m = n
    while m > 0 and a[m-1] == sorted_a[m-1]:
        m -= 1
    k = m
    if k == 0:
        # 整个数组都正确
        print(0)
        return

    # 检查前k个元素是否是循环排列
    temp_a = a[:k]
    temp_b = sorted_a[:k]
    # 判断temp_a是否是temp_b的一个循环移位
    # 将temp_b重复两次，检查temp_a是否是子数组
    double_b = temp_b + temp_b
    found = False
    for i in range(k):
        if double_b[i:i+k] == temp_a:
            found = True
            break
    if found:
        print(1)
        return

    # 如果没有找到满足条件的k，则需要购买两种工具
    print(2)

if __name__ == "__main__":
    main()