def main():
    N = int(input())
    R = list(map(int, input().split()))

    destination = N
    ctr = 1
    while True:
        for idx, r in enumerate(R, 1):
            if r >= destination:
                destination = idx
                break
        if destination == 1:
            break
        ctr += 1

    print(ctr)


if __name__ == "__main__":
    main()