how to add an array to an array, (index location to index location?) to make a multidimensional array in Groovy script

I have two sets of data in two separate lists (I'm using soapui open groovy script) - which has gone through XmlSlurper().parseText() not sure if this matters

a = [c1,c2,c3] 
b = [0 100, 0 50 100, 0 500 1000]

and I want to combine them (location 0 to location 0 then location 1 to location 1 etc) to be like this

c = [[c1,0 100],[c2,0 50 100],[c3,0 500 100]]

The code I have so far

def splitList(list, splitAt) 
{
    list.inject([]) { curr, val ->
    if(curr.size() == 0 || val == splitAt) 
    {
        curr << []
    }
        curr[-1] << val
        curr
    }
}

def c = [a, splitList(b, 0)].transpose()*.flatten()

and when I log.info c I get [[c1,0 100, 0 50 100, 0 500 100]]