# Dutch Auction (Anchor) In a Dutch auction, the seller sets a starting price. The price decreases over time until the buyer buys. Complete all tasks below - Implement a Dutch auction program - Test locally # Update program id ```shell anchor keys sync ``` # Task 1 - Implement [`init`](https://github.com/Cyfrin/solana-course/blob/main/apps/auction/anchor/exercise/programs/auction/src/lib.rs) - Check sell token != buy token - Check start price >= end price - Check current timestamp <= start time < end time - Check sell amount > 0 - Send sell token to `auction_sell_ata` Call `lib::transfer` to send tokens - Store Auction state # Task 2 - Implement [`buy`](https://github.com/Cyfrin/solana-course/blob/main/apps/auction/anchor/exercise/programs/auction/src/lib.rs) - Check auction has started - Check auction has not ended - Calculate price Price should decrease linearly over time from `start_price` to `end_price`. - Check current price is greater than or equal to `end_price` - Check current price is less than or equal to `max_price` - Calculate amount of buy token to send to seller - Send buy token to seller - Send sell token to buyer Call `lib::transfer_from_pda` to send token to buyer - Close `auction_sell_ata` ```shell close_account(CpiContext::new_with_signer( ctx.accounts.token_program.to_account_info(), CloseAccount { account: ctx.accounts.auction_sell_ata.to_account_info(), destination: ctx.accounts.seller.to_account_info(), authority: ctx.accounts.auction.to_account_info(), }, &[seeds], ))?; ``` # Task 3 - Implement [`cancel`](https://github.com/Cyfrin/solana-course/blob/main/apps/auction/anchor/exercise/programs/auction/src/lib.rs) - Send sell token to seller - Close `auction_sell_ata` # Build ```shell anchor build ``` # Test ```shell anchor test ```