import java.util.*;

public class RecursionExamples {
	public static void main(String[] args) {
		printBinary(45);
		System.out.println();
		System.out.println(isPalindrome("madam"));
		System.out.println(isPalindrome("Java"));
	}

	// Returns true if the given string reads the same
	// forwards as backwards.
	// Trivially true for empty or 1-letter strings.
	public static boolean isPalindrome(String s) {
		if (s.length() < 2) {
			return true;	// base case
		} else {
			return s.charAt(0) == s.charAt(s.length() - 1)
				&& isPalindrome(s.substring(1, s.length() - 1));
		}
	}

	// Prints the given integer's binary representation.
	public static void printBinary(int n) {
		if (n < 0) {
			// recursive case for negative numbers
			System.out.print("-");
			printBinary(-n);
		} else if (n < 2) {
			// base case; same as base 10
			System.out.print(n);
		} else {
			// recursive case; break number apart
			printBinary(n / 2);
			printBinary(n % 2);
		}
	}
}