You have number *a*, whose decimal representation quite luckily contains digits 1, 6, 8, 9. Rearrange the digits in its decimal representation so that the resulting number will be divisible by 7.

Number *a* doesn't contain any leading zeroes and contains digits 1, 6, 8, 9 (it also can contain another digits). The resulting number also mustn't contain any leading zeroes.
The first line contains positive integer *a* in the decimal record. It is guaranteed that the record of number *a* contains digits: 1, 6, 8, 9. Number *a* doesn't contain any leading zeroes. The decimal representation of number *a* contains at least 4 and at most 10<sup class="upper-index">6</sup> characters.
from itertools import permutations

q, p = [1, 3, 2, 6, 4, 5], [1, 6, 8, 9]

t = list(map(int, input()))
n = len(t)
m = n - 1

for i in range(4):
    if t[i] != p[i]:
        for j in range(n):
            if t[j] == p[i]:
                t[j], t[i] = t[i], t[j]
                break

s = sum(q[(m - i) % 6] * t[i] for i in range(4, n)) % 7
q = [q[(m - i) % 6] for i in range(4)]

for r in permutations(p):
    if (s + sum(r[i] * q[i] for i in range(4))) % 7 == 0:
        t[: 4] = r
        break

print(''.join(map(str, t)))
