from itertools import pairwise


def sum_to_1digit(num1: int, num2: int) -> int:
    num_summed = num1 + num2
    if num_summed >= 10:
        return sum(map(int, list(str(num_summed))))
    return num_summed


def main():
    for _ in range(int(input())):
        S = list(map(int, list(input())))

        while len(S) > 1:
            S_tmp = []
            for num1, num2 in pairwise(S):
                S_tmp.append(sum_to_1digit(num1, num2))
            S = S_tmp.copy()
        print(S[0])


if __name__ == "__main__":
    main()