The following text was written to the standard output stream when the Expressions Thing program was executed from IntelliJ.
square =
area of the square = 160000.0
perimeter of the square = 1600.0
diagonal of the square = 565.685424949238
disk =
area of the square = 160000.0
area of the disk = 125663.70614359173
perimeter of the square = 1600.0
perimeter of the disk = 1256.6370614359173
diamond =
area of diamond = 80000.0