## Curve V1 Contracts We will discuss the contracts that Curve V1 uses to support its automated market maker (AMM). Curve V1 AMMs are a variation of a base contract called StableSwap. ## StableSwap We will discuss the StableSwap contract by looking at examples of pool contracts: 3pool and stETH. ### 3pool The 3pool contract supports three tokens: DAI, USDC, and USDT. The pool contract name is `StableSwap3pool`. #### N_COINS The `N_COINS` constant is defined as three. This constant is important because we will need to use it when we call a Curve V1 AMM contract. #### addLiquidity The `addLiquidity` function takes an array of tokens as input. The size of the array is determined by the `N_COINS` constant. We will need to ensure that we provide the correct number of tokens when we call this function. ```javascript def add_liquidity(amounts: uint256[N_COINS], min_amount: uint256) -> uint256: ``` ### stETH The stETH contract supports two tokens: ETH and stETH. The pool contract name is `StableSwap stETH`. #### N_COINS The `N_COINS` constant is defined as two. #### addLiquidity The `addLiquidity` function takes an array of tokens as input. The size of the array is determined by the `N_COINS` constant. We will need to ensure that we provide the correct number of tokens when we call this function. ```javascript def add_liquidity(amounts: uint256[N_COINS], min_amount: uint256) -> uint256: ``` ## Summary Curve V1 uses a contract called StableSwap for its AMMs. The pool contracts are variations of this base contract, such as `StableSwap3pool` and `StableSwap stETH`. Each pool contract holds a specific number of tokens, determined by the `N_COINS` constant. We will need to ensure that we provide the correct number of tokens when we interact with these contracts.