make structure(complicatedness)
test structure
repeat


structure elements:
x
y
const
switch(., ., .)
sin(.)
cos(.)
*
/
+
-

switch(x, a, b) = x < 0 ? a : b

complicatedness = number of elements
c(sin(x)) = 2
c(sin(const)) = 2
c(x+y) = 3