Splitting list according to branch index

Hi all, 

Im having a problem in grasshopper (v. 0.8.0066) where I want to split a list into branches according to the index of each item. 

I want all of the "line like curves" with a index starting with 0 ({0;0},{0;1},{0;2}...{0;5}) into one branch and all the ones starting with 1 ({1;0},{1;1},{1;2},{1;3}) into another branch. The number of items vary a lot so I cant simply split the list after a certain number of items.

Lets say I have a list looking like this: 

     {0;0}

x1

     {0;1}

y1

     {0;2}

z1

     {1;0}

x2

     {1;1}

y2

The list Im after should look something like this:

     {0}

x1

y1

z1

     {1}

x2

y2

Does anyone know if there is a way to do this without scripting in C# or anything similar? 

Thanks,
Viktoria