Wrong calculation in function LBRouter._getAmountsIn make user lose a lot of tokens when swap through JoePair (most of them will gifted to JoePair freely)

Lines of code Vulnerability details Vulnerable detail Function LBRouter.getAmountsIn is a helper function to return the amounts in with given amountOut. This function will check the pair of token and tokenNext is JoePair or LBPair using binStep. If binStep == 0, it will be a JoePair otherwise it...