program main
implicit none
integer :: i, j, k, ls, lt
character :: s*50, t*50, u*100

read(*,*) s
read(*,*) t
ls = len(s)
lt = len(t)

do i = 1, ls+lt
   if( mod(i,2) == 1 ) then
      j = i/2 +1
      u(i:i) = s(j:j)
   else
      j = i/2
      u(i:i) = t(j:j)
   end if
end do
write(*,*) u(1:ls+lt)
   



end program main
