I just need to know exactly what the string has in it format wise and an accurate but made up example would do fine. with the understanding that x can be of any length, is your example of P1 -- C1 -- C2 -- P2 -- C3 -- C4 --C5 -- C6 -- P3 -- C7 and accurate example of the string including the dashes and spaces between the nodes? If not, I need to know. This actually isn't a difficult problem to solve but I need to know what the actual format of these strings is like.