Mixing in base 2 P42672

Given a natural number x > 0 with n bits, we denote with x_n−1… x₀ its representation in base 2. For example, x = 8 in base 2 is 1000, so x₃ = 1 and x₂ = x₁ = x₀ = 0.

Write a program to mix the base 2 representations of two given natural numbers x and y with the same number of bits n. That is, print x_n−1 y_n−1 … x₀ y₀.

Input

Input consists of several cases, each with two natural numbers with the same number of bits, between 1 and 30.

Output

For every case, print the mixing of the representations in base 2 of the two numbers.