n = int(input())
ans = 10 ** 50

for _ in range(n):
    v = input()
    lst = []
    for num in v:
        if num in "0123456789":
            lst.append(int(num))
        else:
            lst.append(ord(num) - 55)
    
    p = max(max(lst) + 1, 2)
    total = 0

    for i in range(len(lst)):
        total += (p ** i) * lst[-1 - i]
    ans = min(ans, total)
print(ans)