public class Arrange01 {

    public static void arrange (int [ ] values) {
	int posOfFirst1 = 0;  
	// no zeroes seen yet, so pos of last 0 may be viewed as -1
	for (int k=0; k<values.length; k++) {
	    // elements 0 through k-1 are arranged zeroes first
	    if (values[k] == 0) {
		// exchange values[k] with values[posOfFirst1]
		int temp = values[k];
		values[k] = values[posOfFirst1];
		values[posOfFirst1] = temp;
		// now values[posOfFirst1] is 0, so the first 1 (if any)
		//   is right next to it
		posOfFirst1++;
	    } else {
		// do nothing, since the position of the first 1 hasn't changed
	    }
	    // elements 0 through k are now arranged zeroes first
	}
    }

    public static void println (int [ ] values) {
	for (int k=0; k<values.length; k++) {
	    System.out.print (values[k] + " ");
	}
	System.out.println ( );
    }

    public static void main (String [ ] args) {
	int [ ] values1 = {0, 0, 0, 0, 0};
	int [ ] values2 = {1, 1, 1, 1, 1};
	int [ ] values3 = {1, 0, 1, 0, 0};
	arrange (values1);
	println (values1);
	arrange (values2);
	println (values2);
	arrange (values3);
	println (values3);
    }
}