#include <iostream>
#include <fstream>
#include <string>
using namespace std;

int main()
{
	ifstream in("Input.txt");
		ifstream in2("Input2.txt");
		ofstream out("Output.txt");

		float s;string s1,s2;

		while (in.peek()!=EOF)
		{
			getline(in,s1);
				getline(in2,s2);
		for (int i=0;i<s1.size();i++)
		{
			for (int j=0;j<s2.size();j++)

			{
				s=s1[i]+s2[j];
				++i;++j;
			}
		}
		out<<s/2<<endl;