题解 | #字符串合并处理#

def step_1(a,b):#第一步操作
    c=str(a)+str(b)
    return c

def step_2(a):#第二步操作
    odd=[]
    even=[]
    for i in range(len(a)):
        if i%2 == 0:
            even.append(a[i])
        else:
            odd.append(a[i])
    odd=sorted(odd)
    even=sorted(even)
    b=[]
    for i in range(len(a)):
        if i%2 ==0:
            j=int(i/2)
            b.append(even[j])
        else:
            j=int((i-1)/2)
            b.append(odd[j])
    c=''.join(b)
    return str(c)

def step_3(a):#第三步操作
    dic=['0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F']
    f=''
    for i in a:
        if i.isdigit() :
            b=bin(int(i))[2:].zfill(4)
            c=b[::-1]
            d=int(c,2)
            e=dic[d]
            f+=str(e)
        elif i.isalpha() and i.upper() in dic:
            for j in range(len(dic)):
                if dic[j]==i.upper():
                    b=bin(j)[2:].zfill(4)
                    break
            c=b[::-1]
            d=int(c,2)
            e=dic[d]
            f+=str(e) 
        else:
            f+=str(i)
    return f

str_1,str_2=input().split()
str_3=step_1(str_1,str_2)
str_4=step_2(str_3)
str_5=step_3(str_4)
print(str_5)