MultipleOfThree.java

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/**
 *
 * @author dube_
 */
public class MultipleOfThree {

    static int getNumber(String binary_number) {
	int number = 0;
	for (int i = binary_number.length() - 1; i >= 0; i--) {
	    number += Integer.parseInt("" + binary_number.charAt(i)) * Math.pow(2, binary_number.length() - i - 1);
	}
	return number;
    }

    static boolean is_multiple(String binary_number) {

//	100000
	int number = getNumber(binary_number);
	return number % 3 == 0;
    }

    static String reverseString(String string) {
	StringBuilder b = new StringBuilder(string);
	return b.reverse().toString();
    }

    static int performCut(String binary_number) {
	int multiple_of_three = 0;
	String longest_string = "";
	int number_cuts = 0;
	//1000000011
	for (int i = 0; i < binary_number.length(); i++) {
	    for (int j = i + 1; j < binary_number.length(); j++) {

		if (is_multiple((binary_number.substring(i, j)))) {
		    longest_string = binary_number.substring(i, j);
		}

	    }
	    binary_number = binary_number.replace(longest_string, "");

	    if (!longest_string.isEmpty()) {
		number_cuts++;
		System.out.println(longest_string);
	    }
	    longest_string = "";
	}
	return number_cuts;
    }

    public static void main(String[] args) {
	System.out.println(performCut("1010001111001"));
    }
}