Optimise binary arithmetic operations for powers of 10

[faheel]

Optimise binary arithmetic operations for powers of 10

[KingAkeem]

Would I be able to work on this?

[faheel]

@KingAkeem Sure, go ahead!

[KingAkeem]

I'm not sure how you want the multiply to be optimized, I attempted to just append zeros based on the size of the number but that's much slower than normal multiplication. I don't think we can make it more optimized than the compiler without writing ASM.

[faheel]

Say you have num1 and num2 as the two BigInt operands. Then, if any one of them is found to be a power of 10 (say it's num1), you can append the zeroes at once instead of using a loop, like so:

num2.value.append(num1.value.begin() + 1, num1.value.end());

This will certainly be much faster than simply carrying on with the multiplication.

[KingAkeem]

I should've thought a little more about how I could utilize the BigInt objects first. I'm going to try both of those out right now.

[Aakankshareddy]

Hi,would like to contribute. Should I implement it in math.hpp or create a separate file?

[faheel]

@Aakankshareddy The operators have already been defined in operators/binary_arithmetic.hpp. You have to add checks within the definitions of the operators that are mentioned at the top, using a function named is_power_of_10(), which you can define in functions/utilities.hpp.

[MagmaCode]

I gave it a try. Hope it is good enough.
The tests pass and run times also seem to have decreased, which is good.