N2 - Rounding up during while buying tokens or adding liquidity can be avoided about niftyswap

[PhABC]

This is a good suggestion, though I believe the rounding errors will be small enough that it won't really be an issue. Happy to be convinced otherwise!

[Agusx1211]

Rounding errors should be small enough for most of the tokens, but isn’t unheard of ERC20 tokens that have no decimals and end up with a minimal fragmentation unit of 1 dollar or so, and if a token like that were to be traded on Niftyswap it would be inefficient.

Also, the rounding on getBuyPrice could lead to lots of trades of round numbers to increase by 1 wei, maybe that could cause some confusion?

Last but not least, I think that is a simple fix that barely increases the gas usage of the contract.

[PhABC]

ccc6e9d introduces a slightly difference method than commit above ^