@Test
public void success_toMutualOppositeForm() {

    BigInteger integer1 = new BigInteger("27");
    BigInteger integer2 = new BigInteger("11");
    BigInteger integer3 = new BigInteger("247");
    BigInteger integer4 = new BigInteger("327");
    int[] result1 = ArrayUtils.toMutualOppositeForm(integer1);
    int[] result2 = ArrayUtils.toMutualOppositeForm(integer2);
    int[] result3 = ArrayUtils.toMutualOppositeForm(integer3);
    int[] result4 = ArrayUtils.toMutualOppositeForm(integer4);
    assertThat(result1, is(new int[]{1, 0, -1, 1, 0, -1}));
    assertThat(result2, is(new int[]{1, -1, 1, 0, -1}));
    assertThat(result3, is(new int[]{1, 0, 0, 0, -1, 1, 0, 0, -1}));
    assertThat(result4, is(new int[]{1, -1, 1, -1, 0, 0, 1, 0, 0, -1}));
}