s = str(input())
import itertools
n = len(s)
ans = int(s)
for p in itertools.permutations(range(n), 2):
    i0, i1 = p[0], p[1]
    t = []
    for c in s:
        t.append(c)
    t[i0], t[i1] = t[i1], t[i0]
    t = ''.join(t)
    t = int(t)
    ans = max(ans, t)
print(ans)