两个集合求对称差集

public static int distinctElementCount(int arr1[], int arr2[])
    {
        if (arr1.length == 0) {
            return arr2.length;
        }
        if (arr2.length == 0) {
            return arr1.length;
        }
        int count = 0;
        Arrays.sort(arr1);
        Arrays.sort(arr2);
        int i=0,j=0, same = -1;
        while (i< arr1.length && j<arr2.length) {
            if (arr1[i] == arr2[j]) {
                same = arr1[i];
                i++;j++;
            } else if (arr1[i] == same) {
                i++;
            } else if (arr2[j] == same) {
                j++;
            } else if (arr1[i] < arr2[j]) {
                i++;
                count++;
            } else {
                j++;
                count++;
            }
        }
        count += arr1.length + arr2.length - i - j;

        return count;
    }

    @Test
    public void testDistinct() {
        Assert.assertEquals(6, distinctElementCount(new int[]{1,2,3,4}, new int[]{4,5,6,7}));
        Assert.assertEquals(7, distinctElementCount(new int[]{4,3,5,6}, new int[]{3,2,1,6,3,9,8,13}));
        Assert.assertEquals(12, distinctElementCount(new int[]{1,2,3,4,5,6,7,8,9,10}, new int[]{11,12,13,4,5,6,7,18,19,20}));
    }