def biggerIsGreater(w):
    if "".join(sorted(list(w), reverse=True)) == w:
        return "no answer"
    i1 = len(w) - 2
    while w[i1] >= w[i1 + 1]:
        i1 -= 1
    i2 = len(w) - 1
    while w[i2] <= w[i1]:
        i2 -= 1
    left = list(w)[:i1]
    changed = list(w[i1:])
    changed[0], changed[i2 - i1] = changed[i2 - i1], changed[0]
    middle = changed[0:1]
    right = changed[1:]
    right.sort()
    return "".join(left + middle + right)