n = [int(x) for x in input()]

for i,ni in enumerate(n):
    tr = 0
    idx = i
    for j,nj in enumerate(n[i:]):
        if nj >= tr:
            tr = nj
            idx = i + j
    if tr > ni:
        n[idx] = ni
        n[i] = tr
        break

print(''.join([str(x) for x in n]))