def second_biggest_number(n):
    bigest_number = 0
    second_bigest = 0

    if n  < 2:
        print("please use bigger parameter")

    for i in range(n):
        x = int(input())
        if i == 0 and x < 0:
            bigest_number = x

        if x > bigest_number:
            second_bigest = bigest_number
            bigest_number = x
        elif bigest_number > x and x > second_bigest:
            second_bigest = x

    print(second_bigest)


second_biggest_number(4)