Share 'Selective loft'

Hi guys! My problem may appear very easy to solve, but i still didn't find a way: I've a branch of flatten data like that: {0} 0 Poly Curve 1 Poly Curve 2 Poly Curve 3 Poly Curve 4 Poly Curve 5 Poly Curve 6 Poly Curve 7 Poly Curve ... etc I need to loft half of them as a pattern like 2 by 2... ex: 0 with 1 ---> loft 1 with 2 ---> no loft 2 with 3 ---> loft 3 with 4 ---> loft  4 w..…