# Constant Sum AMM (Anchor) Build a constant sum AMM. Liquidity providers deposit token A and token B. Traders can swap token A or B for the other token at 1 to 1 exchange rate. Complete all tasks below - Implement a constant sum AMM program - Test locally # Update program id ```shell anchor keys sync ``` # Task 1 - Implement [`init_pool`](https://github.com/Cyfrin/solana-course/blob/main/apps/amm/anchor/exercise/programs/amm/src/lib.rs) - Check `fee` <= `constants::MAX_POOL_FEE` - Check `mint_a.decimals` == `mint_b.decimals` - Store Pool state # Task 2 - Implement [`add_liquidity`](https://github.com/Cyfrin/solana-course/blob/main/apps/amm/anchor/exercise/programs/amm/src/lib.rs) - Calculate user shares to mint - Transfer `amount_a` from user into `pool_a` - Transfer `amount_b` from user into `pool_b` - Mint shares to user's associated token account (`payer_liquidity`) # Task 3 - Implement [`remove_liquidity`](https://github.com/Cyfrin/solana-course/blob/main/apps/amm/anchor/exercise/programs/amm/src/lib.rs) - Calculate the amount of token a and b to withdraw - Check `amount_a` >= `min_amount_a` - Check `amount_b` >= `min_amount_b` - Burn user's shares - Transfer `amount_a` from pool to `payer_a` (user's associated token account for token a) - Transfer `amount_b` from pool to `payer_b` (user's associated token account for token b) # Task 4 - Implement [`swap`](https://github.com/Cyfrin/solana-course/blob/main/apps/amm/anchor/exercise/programs/amm/src/lib.rs) - Calculate amount out with fee - Check `amount_out` >= `min_amount_out` - Transfer token in from user to pool - Transfer token out from pool to user # Build ```shell anchor build ``` # Test ```shell anchor test ```