题解 | #字符串合并处理#

import sys
def odd_even_sort(s):
    even_indexs=[]
    odd_indexs=[]
    for i,val in enumerate(s):
        if i%2==0:
            even_indexs.append(val)
        else:
            odd_indexs.append(val)
    even_indexs.sort()
    odd_indexs.sort()
    index_sort=even_indexs
    for i,val in enumerate(odd_indexs):
        index_sort.insert((i+1)*2-1,val)
    return index_sort


def transition(s):
    l1='abcdefABCDEF'
    l2='123456789'
    dic1={'a':10,'A':10,'b':11,'B':11,'c':12,'C':12,'d':13,'D':13,'e':14,"E":14,'f':15,'F':15}
    dic2={10:'A',11:'B',12:'C',13:'D',14:'E',15:'F'}
    for i,val in enumerate(s):
        if val in l1 or val in l2:
            if val in  l1:
                x=dic1[val]
            else:
                x=int(val)
            binx=bin(x)[2:].zfill(4)[::-1]
            val=int(binx,2)
            if val>9:
                val=dic2[val]
        s[i]=str(val)
    return s
        

for line in sys.stdin:
    s= ''.join(line.strip().split(' '))
    index_sort=odd_even_sort(s)
    x=transition(index_sort)
    print(''.join(x))