Blockchain

Understanding Zero-Knowledge Proofs 🔐 Zero-Knowledge Proof (ZKP) is a revolutionary cryptographic method that allows one party (the prover) to prove to another party (the verifier) that they know specific information without revealing any details about that information. Key Characteristics Privacy Protection 🛡️: The prover can convince the verifier they know something without revealing what it is, maintaining complete privacy. Verifiability ✅: The verifier can be certain the prover knows the information without learning anything about the actual information itself. ...

What is a Mapping in Solidity? 🗺️ A mapping in Solidity is a powerful key-value data structure that functions like a hash table or dictionary in traditional programming languages. It’s the go-to solution for associating wallet addresses with balances and managing relationships between different data types on the blockchain. Mappings are essential building blocks in Solidity, particularly for storing and managing critical data such as user balances, permissions, and any other relationship between two types of data. ...

Learn how to create your first simple Solidity smart contract using the popular Remix IDE. This tutorial covers the most basic contract that’s often introduced in Solidity learning resources. The contract functionality is straightforward: set a number and retrieve it. Even this simple operation consumes gas fees, which we’ll verify in a local EVM test environment. Creating Your First Smart Contract with Remix IDE 1. Access Remix IDE Visit https://remix.ethereum.org/ Ensure the Environment is set to [Remix VM (London)] for local testing. ...

Solidity SafeMath Library: Secure Arithmetic Operations 🔒 The SafeMath library provides secure arithmetic operations that prevent overflow and underflow vulnerabilities using assert statements. /** * @title SafeMath * @dev Math operations with safety checks that throw on error */ library SafeMath { /** * @dev Multiplies two numbers, throws on overflow. */ function mul(uint256 a, uint256 b) internal pure returns (uint256) { if (a == 0) { return 0; } uint256 c = a * b; assert(c / a == b); return c; } /** * @dev Integer division of two numbers, truncating the quotient. */ function div(uint256 a, uint256 b) internal pure returns (uint256) { // assert(b > 0); // Solidity automatically throws when dividing by 0 uint256 c = a / b; // assert(a == b * c + a % b); // There is no case in which this doesn't hold return c; } /** * @dev Substracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend). */ function sub(uint256 a, uint256 b) internal pure returns (uint256) { assert(b <= a); return a - b; } /** * @dev Adds two numbers, throws on overflow. */ function add(uint256 a, uint256 b) internal pure returns (uint256) { uint256 c = a + b; assert(c >= a); return c; } } /** * @title SafeMath32 * @dev SafeMath library implemented for uint32 */ library SafeMath32 { function mul(uint32 a, uint32 b) internal pure returns (uint32) { if (a == 0) { return 0; } uint32 c = a * b; assert(c / a == b); return c; } function div(uint32 a, uint32 b) internal pure returns (uint32) { // assert(b > 0); // Solidity automatically throws when dividing by 0 uint32 c = a / b; // assert(a == b * c + a % b); // There is no case in which this doesn't hold return c; } function sub(uint32 a, uint32 b) internal pure returns (uint32) { assert(b <= a); return a - b; } function add(uint32 a, uint32 b) internal pure returns (uint32) { uint32 c = a + b; assert(c >= a); return c; } } /** * @title SafeMath16 * @dev SafeMath library implemented for uint16 */ library SafeMath16 { function mul(uint16 a, uint16 b) internal pure returns (uint16) { if (a == 0) { return 0; } uint16 c = a * b; assert(c / a == b); return c; } function div(uint16 a, uint16 b) internal pure returns (uint16) { // assert(b > 0); // Solidity automatically throws when dividing by 0 uint16 c = a / b; // assert(a == b * c + a % b); // There is no case in which this doesn't hold return c; } function sub(uint16 a, uint16 b) internal pure returns (uint16) { assert(b <= a); return a - b; } function add(uint16 a, uint16 b) internal pure returns (uint16) { uint16 c = a + b; assert(c >= a); return c; } } Usage Best Practices When using this library, it’s recommended to replace increment operators like ++ with SafeMath’s .add(1) method. ...

Understanding ERC20 Token Standard in Solidity The ERC20 standard is a specification for tokens that operate on the Ethereum blockchain. It defines a common set of rules that all Ethereum-based tokens must follow, ensuring compatibility across different platforms and applications. What is ERC20? 🤔 ERC20 is a technical standard used for smart contracts on the Ethereum blockchain that implements a common list of rules for Ethereum tokens. This standard allows developers to create tokens that are compatible with the broader Ethereum ecosystem. ...

Solidity Data Types: Complete Guide for Smart Contract Development Solidity is a statically-typed programming language designed for writing smart contracts on the Ethereum blockchain. This means you must specify the data type of every variable when declaring it, which helps the compiler catch errors and ensures your code is both safe and efficient. Understanding data types is fundamental to smart contract development. Let’s explore the most commonly used data types in Solidity: ...