import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.List;

public class Test {

	public static void main(String[] args) {
		String[] arr = new String[] { "0,1", "1,10", "0,100", "xx", "1,2" };
		Arrays.sort(arr, new Comparator<String>() {
			@Override
			public int compare(String o1, String o2) {
				if (o1.indexOf(",") == -1 || o2.indexOf(",") == -1) {
					return 0;
				}
				String[] temp1 = o1.split(",");
				String[] temp2 = o2.split(",");
				if (temp1[0].equals(temp2[0])) {
					return Integer.parseInt(temp1[1]) - Integer.parseInt(temp2[1]);
				} else {
					return Integer.parseInt(temp1[0]) - Integer.parseInt(temp2[0]);
				}
			}
		});
		System.out.println(Arrays.toString(arr));
		List<String> list1 = new ArrayList<String>();
		List<String> list2 = new ArrayList<String>();
		List<String> list3 = new ArrayList<String>();
		for (int i = 0; i < arr.length; i++) {
			if (arr[i].indexOf(",") == -1 || "0".equals(arr[i].split(",")[0])) {
				list1.add(arr[i]);
			} else {
				list2.add(arr[i]);
			}
		}
		int maxLength = Math.max(list1.size(), list2.size());
		for (int i = 0; i < maxLength; i++) {
			if (i > list1.size() - 1) {
				list3.add("");
				list3.add(list2.get(i));
			} else if (i > list2.size() - 1) {
				list3.add(list1.get(i));
				list3.add("");
			} else {
				list3.add(list1.get(i));
				list3.add(list2.get(i));
			}
		}
		System.out.println(Arrays.toString(list3.toArray()));
	}

}