I don't think f-ck all can be four, so it must be zero, and the same as sod all.
Just noticed the alliteration: Square root: Sod, Five: F-uck.
At the risk of a complete thread derail and the wrath of @scrumpymike*, are there any other expressions for nothing that have equivalent additions?
The wrath of Mike is a terrible thing - you are denied any crumble!