@zk-kit/lean-imt.sol/README.md

Incremental Merkle tree implementations in Solidity.

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         Lean Incremental Merkle Tree (Solidity)
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    <p align="center">Lean Incremental Merkle tree implementation in Solidity.</p>
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> [!NOTE]  
> This library has been audited as part of the Semaphore V4 PSE audit: https://semaphore.pse.dev/Semaphore_4.0.0_Audit.pdf.

The LeanIMT is an optimized binary version of the [IMT](https://github.com/privacy-scaling-explorations/zk-kit.solidity/tree/main/packages/imt) into binary-focused model, eliminating the need for zero values and allowing dynamic depth adjustment. Unlike the IMT, which uses a zero hash for incomplete nodes, the LeanIMT directly adopts the left child's value when a node lacks a right counterpart. The tree's depth dynamically adjusts to the count of leaves, enhancing efficiency by reducing the number of required hash calculations. To understand more about the LeanIMT, take a look at this [visual explanation](https://hackmd.io/@vplasencia/S1whLBN16).

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## 🛠 Install

### npm or yarn

Install the `@zk-kit/lean-imt.sol` package with npm:

```bash
npm i @zk-kit/lean-imt.sol --save
```

or yarn:

```bash
yarn add @zk-kit/lean-imt.sol
```

## 📜 Usage

Please, see the [test contracts](./test) for guidance on utilizing the libraries.