#include <iostream>
#include <string>
using namespace std;
string file_read_func()
{
string input;
string ret;
while (!cin.eof())
{
cin >> input;
if (!cin.eof())
{
ret += input;
cin >> input;
ret += input + " ";
}
}
return ret;
}
int main() {
std::cout << file_read_func();
}
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