In Java.

Write a program that takes a positive integer n (in decimal) as a command-line argument and prints its binary representation. Recall, in Program 1.3.7, that we used the method of subtracting out powers of 2. Now, use the following simpler method: repeatedly divide 2 into n and read the remainders backward. First, write a while loop to carry out this computation and print the bits in the wrong order. Then use recursion to print the bits in the correct order.

From: Introduction to Programming in Java Robert Sedgewick