N = list(map(int, ''.join(input())))
mn = max(N)
for i in reversed(range(1, len(N))):
    if N[i] == mn:
        for j in range(i):
            if N[j] != mn:
                N[j], N[i] = N[i], N[j]
                break
        break
print(*N, sep='')