def calc(s):
    while len(s) > 1:
        lst = []
        for i in range(len(s) - 1):
            n = int(s[i]) + int(s[i + 1])
            if n >= 10:
                n = 1 + n % 10
            lst.append(str(n))
        s = "".join(lst)
    return s


t = int(input())
for i in range(t):
    s = input()
    ans = calc(s)
    print(ans)