n = int(input())

for i in range(n):
    s = [int(c) for c in input()]
    while len(s) > 1:
        s = [s[k] + s[k + 1] for k in range(len(s) - 1)]
        for (m, x) in enumerate(s):
            if x > 9:
                s[m] -= 9
    print(s[0])