Challenge 4 - Fee Adjusted Swap Input

MediumCPMMFees4 / 20

Challenge 4: Fee Adjusted Swap Input

Real CPMMs usually apply a fee before the input amount touches the swap formula.

Task

Implement fee_adjusted_input(x_in).

Rules

Fee = 30 basis points.
10_000 basis points = 100%.
Effective input = x_in * 9_970 / 10_000.

Example

x_in = 1000
1000 * 9970 / 10000 = 997

This challenge isolates fee math so you can reuse it in later swap logic.

LanguageRust

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Challenge 4 - Fee Adjusted Swap Input · CPMM Exercise | learn.sol