def nextGreat(numlist,N):

    for i in range(N-1,0,-1):
        if numlist[i] > numlist[i-1]:
            break

    answer = numlist[i-1]
    small = i
    for j in range(i+1,N):
        if numlist[j] > answer and numlist[j] < numlist[small]:
            small = j


    numlist[small],numlist[i-1] = numlist[i-1], numlist[small]


    answer=int(str(''.join(map(str,numlist)))[:i])

    numlist = sorted(numlist[i:])

    for j in range(N-i):
        answer = answer * 10 + int(numlist[j])


    print(answer)

input1=3
input2="182"

numlist = list(input2)
nextGreat(numlist, input1)