def f(n, m):
    # print(n, m)
    if not n: return
    print(m[-1], end="")
    if len(n) == 1:

        return

    left, right = n.split(m[-1])
    f(left, m[:len(left)])
    f(right, m[len(left):-1])

mind = input()
last = input()
f(mind, last)