The yield keyword is used to create generators, generate values on demand, and save memory. 1. Replace return to generate finite sequences, such as Fibonacci sequences; 2. Implement infinite sequences, such as natural sequences; 3. Process big data or file readings, and process them line by line to avoid memory overflow; 4. Note that the generator can only traverse once, and can be called by next() or for loop.

BTC, USDT and USDC are three core assets with complementary functions in the crypto ecosystem. BTC is the "spear" of high risk and high returns, and the goal is wealth growth. Stablecoins are defensive "shields", with the goal of preserving value and providing liquidity. For investors seeking long-term capital appreciation, BTC is the core option. Stablecoins are an essential tool for users who want to flexibly operate, manage risks or earn stable returns in the crypto market, with USDC being more favored by conservative users due to its robustness.

The most popular tracks for new funds currently include re-staking ecosystems, integration of AI and Crypto, revival of the Bitcoin ecosystem and DePIN. 1) The re-staking protocol represented by EigenLayer improves capital efficiency and absorbs a large amount of long-term capital; 2) The combination of AI and blockchain has spawned decentralized computing power and data projects such as Render, Akash, Fetch.ai, etc.; 3) The Bitcoin ecosystem expands application scenarios through Ordinals, BRC-20 and Runes protocols to activate silent funds; 4) DePIN builds a realistic infrastructure through token incentives to attract the attention of industrial capital.

Semaphore is used to control the number of concurrent accesses, suitable for resource pool management and flow-limiting scenarios, and control permissions through acquire and release; CountDownLatch is used to wait for multiple thread operations to complete, suitable for the main thread to coordinate child thread tasks. 1. Semaphore initializes the specified number of licenses, supports fair and non-fair modes, and when used, the release should be placed in the finally block to avoid deadlock; 2. CountDownLatch initializes the count, call countDown to reduce the count, await blocks until the count returns to zero, and cannot be reset; 3. Select according to the requirements: use Semaphore to limit concurrency, wait for all completions to use CountDown

The steps to install PHP8 on Ubuntu are: 1. Update the software package list; 2. Install PHP8 and basic components; 3. Check the version to confirm that the installation is successful; 4. Install additional modules as needed. Windows users can download and decompress the ZIP package, then modify the configuration file, enable extensions, and add the path to environment variables. macOS users recommend using Homebrew to install, and perform steps such as adding tap, installing PHP8, setting the default version and verifying the version. Although the installation methods are different under different systems, the process is clear, so you can choose the right method according to the purpose.

The most promising small currencies in 2025 include Arbitrum (ARB), Render (RNDR), Sui (SUI), Ondo Finance (ONDO), and Immutable (IMX). 1.Arbitrum, as an Ethereum Layer 2 expansion solution, occupies a dominant market position with its technological advantages and ecological scale; 2. Render combines AI and decentralized GPU rendering to meet the rapidly growing computing power needs; 3. Sui is based on a high-performance public chain architecture, suitable for large-scale application scenarios such as games and social networking; 4. Ondo Finance promotes the tokenization of real-world assets, connecting traditional finance and digital assets; 5. Immu

The core reasons why USDC becomes the focus of the market in 2025 include: 1. Leading regulatory compliance. Circle actively embraces supervision and holds a variety of international payment licenses, making it the first choice for traditional institutions to enter the crypto field; 2. Application scenarios have expanded from transaction tools to cross-border payments, corporate settlement and other fields, with high efficiency and low cost advantages; 3. As the cornerstone asset of the DeFi ecosystem, it is widely used for lending, pledge and liquidity provision; 4. Adopted by traditional financial giants such as Visa and Mastercard, promoting them to become an important part of future financial infrastructure.

As a key bridge connecting the crypto world with real fiat currencies, stablecoins have become an indispensable infrastructure in the field of digital assets. However, facing the wide range of stablecoins in the market, especially the two giants of USDT and USDC, many users will be confused: Are they really safe? How to choose between the two? This article will conduct in-depth analysis of the security of stablecoins and conduct a comprehensive comparison of USDC and USDT.