Ethereum: Algorithm of checking whether an element is present in a merkle tree

Ethereum Merkle Tree Implementation: Check the presence

Merle trees have become an important data structure in the Ethereum ecosystem, so that programmers can efficiently check and download large data records. The algorithm that is used to check whether there is a certain element in the Merle tree is “the algorithm of the check as to whether the element is available” or simply “IS_Presser -Method (element)” “.

What is a Merle tree?

Merle Tree is a binary tree structure that enables efficient data integrity and authentication. It consists of many leaves, each of which represents a block or a transaction on the Ethereum blockchain. The main node of the tree contains all leaf nodes that create a hierarchical structure.

is_Present algorithm (element)

In order to check whether the element is available in the Merle tree, we have to cross the tree from the root to leaf nodes and check whether each sublist rooted in a position contains a certain element. The algorithm takes a few steps:

• Basic case: If the value of the current node fits the target element, return True.

• Recursive case:

  Otherwise it causes “IS_Presser (element)on the left child (if available) and the right child (if available). If either a recursive connection really turns around, they return.

Implementation in reliability

Here is an example of the implementation of the "IS_PRESENT (element) function in solidity:

Solidity

Pragma solidity ^0.8.0;

Merkletre Treaty {

// board for saving all leaves (blocks or transactions) in a tree

Mapping (address => uint256 []) public leaves;

// function for creating a new leaf node

Createleaf Function (_node Address, Uint256 [] Memory _Data) Public {

Leaves [_node] .push (_data);

}

// Function to check whether the element in the Merle tree exists

ISpresent (uint256 _eement) function.

// Basic case: If the value of the current node fits the target element, return True.

if (leaves [msg.sender] [0] == _element) {

return;

}

// fall back: otherwise they call "IS_Presser (element) on the left child recursively (element)

// and the right child. If either a recursive connection really turns around, they return.

for (uint256 i = 1; i

if (leaves [msg.sender] [i] == _element) {

return;

}

ifspresent (_element)) {

return;

}

}

// If you don’t have a fit, return false.

return false;

}

}

`

Explanation and left

* Data structure of Merkle Tree : This article contains a detailed explanation of the Merku tree data structure and its implementation in reliability. [Further information: Ethereum Blockchain basics] (

* IS_PRESENT function : This function implements the IS_PRESENT (element) algorithm so that you can check whether the element is available in the Merle tree. [Solive Tabs: How to Implement the ISpresent function] (

! [Ethereum blockchain tutorial: How to create a Merkle-Baum] (

Additional resources

* Implementation of the Merkle -Baumes : This article contains more detailed information on the implementation of the IS_PRESET function using a different approach.

* [Solidity tutorial: Understanding and implementation of Merkle trees] (