/**输入abc ABC,输出aAbBcB****/
#include<iostream>
#include<string>
using namespace std;
class STRING
{
int n;
string string1,string2,string12;
public:
STRING(string str1,string str2)
{
string1=str1;
string2=str2;
}
void exchange();
void print()
{
cout<<string12<<endl;
}
};
void STRING::exchange()
{
n=strlen(string1.c_str());
cout<<n<<endl;
for(int i=0;i<n;i++)
{
char strtemp=string1[i];
char strtemp2=string2[i];
string12+=strtemp;
string12+=strtemp2;
}
}
int main(int argc,char *argv[])
{
string strr1,strr2;
cin>>strr1>>strr2;
STRING str(strr1,strr2);
str.exchange();
str.print();
STRING str2(strr2,strr1);
str2.exchange();
str2.print();
return 0;
}