Hi Shubham,
You can use the following sample CGA Rule
/**
* File: split.cga
* Created: 8 Mar 2019 05:09:16 GMT
* Author: Imran Khan
*/
version "2018.0"
attr height = 1200
attr floor_ht = height/3
Footprint -->
extrude(height)
split(y){floor_ht:groundFloor|floor_ht:middleFloor|floor_ht:topFloor}
groundFloor -->
color (0.3,0.3,0.2,0.5)
x.
middleFloor -->
color (0.3,0.5,0.8,0.5)
s(400,400,800)
center(xz)
x.
topFloor -->
color (0.3,0.5,0,0.5)
s(200,200,400)
center(xz)
x.
The Output will be