Mathematica, 98101 bytes
a-a
a/a
⌊E⌋
⌈E⌉
⌈π⌉
⌊E+E⌋
⌈E+E⌉
⌊E*E⌋
⌈E*E⌉
⌈E*π⌉
⌈π*π⌉
⌊π*π^π/E⌋
I'm pretty sure some of these are suboptimal. Those rounding brackets are really expensive.
For consistency, the first onetwo could also be E-E
and E/E
of course, but I thought it's quite nifty to get 0
and 1
from a computation with undefined variables.