def fortune_telling(s):
    current = [int(c) for c in s]
    while len(current) > 1:
        next_current = []
        for i in range(len(current) - 1):
            total = current[i] + current[i + 1]
            if total >= 10:
                total -= 9
            next_current.append(total)
        current = next_current
    return current[0]

T = int(input())
for _ in range(T):
    S = input().strip()
    print(fortune_telling(S))