Disclaimer: I suck at maths. My terminology is potentially all wrong :oops:
Anyway can I make all possible permutations of a calculation just by changing the order of operators and operands?
e.g
step 1 permutate the operators
5, 10, 20 + +
5, 10, 20 + -
5, 10, 20 - -
step 2 permutate order...