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.
def nextPermutation(a) :

    pos=len(a)-2

    while pos>=0 and a[pos]>=a[pos+1] :

        pos-=1

    if pos<0 :

        return False

    else :

        l, r=pos+1, len(a)-1
        nextPos=-1

        while l<=r :

            mid=(l+r)//2

            if a[mid]>a[pos] :

                l=mid+1
                nextPos=mid
            else :

                r=mid-1

        a[pos], a[nextPos]=a[nextPos], a[pos]

    a=a[:pos+1]+sorted(a[pos+1:])

    return a


last=[1, 6, 8, 9]
cnt=[0 for i in range(10)]

for dig in last :

    cnt[dig]-=1


s=input()

for c in s :

    cnt[int(c)]+=1

rem=0
right, zero="", ""

for dig in range(1, 10) :

    while cnt[dig] :

        rem=(rem*10+dig)%7
        cnt[dig]-=1

        right+=str(dig)

while cnt[0] :

    zero+='0'
    cnt[0]-=1

while last :

    t="".join(str(dig) for dig in last)

    curRem=rem

    for dig in last :

        curRem=(curRem*10+dig)%7

    if curRem%7==0 :

        print(right+t+zero)
        exit()

    last=nextPermutation(last)
