#!/bin/python

def check(numbers, num):
    for i in numbers:
        for j in numbers:
            print(f"Checking {i} + {j} = {num}")
            if i + j == num:
                return True

    return False

def rotate(numbers, num):
    del numbers[0]
    numbers.append(num)
    return numbers

with open("input", 'r') as input:
    numbers = []
    for _ in range(26):
        numbers.append(int(next(input).strip()))

    for num in input:
        num = int(num.strip())
        if not check(numbers, num):
            print(num)
            break

        numbers = rotate(numbers, num)