题解 | #字符串合并处理#

from pickle import TRUE
import sys

def isOushu(num):
    if num%2 ==0:
        return True
    else:
        return False
while True:
    try:
        str1,str2 =input().split()
        #1、合并
        s = str1+str2
        s = list(s)
        #2、排序
        n = len(s)
        s1,s2 =[],[]
        l1,l2 =[],[]
        ns =s
        for i in range(n):
            if isOushu(i):
                s1.append(s[i])
                l1.append(i)
            else:
                s2.append(s[i])
                l2.append(i)
        s1.sort()
        s2.sort()
        sn1,sn2 =len(s1),len(s2)
        for i in range(sn1):
            inx = l1[i]
            vua = s1[i]
            ns[inx] =vua
        for i in range(sn2):
            inx = l2[i]
            vua = s2[i]
            ns[inx] =vua
        
        #3、转换
        base='0123456789abcdefABCDEF'
        rs =''
        for i in ns:
            if i in base:
                bstr =bin(int(i,16))[2:].rjust(4,'0')[::-1]
                hstr =hex(int(bstr,2))[2:].upper()
                rs+=hstr
            else:
                rs+=i
        print(rs)
    except:
        break