@Test
public void indexOfHetroAt0() {

    int[] cycle = new int[]{3, 2, 1, 4, 5, 3};
    int[] contr = new int[]{1, 1, 1, 1, 1, 1};
    contr[cycle[0]] = 2;
    Assert.assertEquals(0, MmffAromaticTypeMapping.indexOfHetro(cycle, contr));
}