import sys

for line in sys.stdin:
    lst = list(line.split('\n')[0])
    output = []
    for i in lst:
        output.append([ord(i), i])
    k = j = 0
    for k in range(len(output)):
        for j in range(len(output)):
            if output[j][0] >= output[k][0]:
                output[k], output[j] = output[j], output[k]
    outstr = ''
    for i in output:
        outstr += i[1]
    
    print(outstr)

先做了个二维list,然后按ord之后的那一列排序,再将新list原文本那一列+=到字符串输出。估计是笨办法,但是先过了。