题解 | #字符串排序#

line = input().strip()
ch_list = []
symbol_index = []
for index, ch in enumerate(line):
    if ch.isalpha():
        ch_list.append((ch,ord(ch.lower())*len(line) + index))
    else:
        symbol_index.append((ch, index))
ch_list = sorted(ch_list, key = lambda x:x[1])
result = []
for ch, index in ch_list:
    result.append(ch)
for ch, index in symbol_index:
    result.insert(index, ch)
print(''.join(result))