How to Design a Min Stack with O(1) getMin() Using Two Stacks

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A Min Stack is a data structure that supports push, pop, top, and getMin() operations, all in O(1) time. The naive approach retrieves the minimum by scanning all elements on each call, resulting in O(N) time for getMin(). The optimized solution uses two stacks: a main stack for all values and an auxiliary min stack that tracks the running minimum at every stage. When a new element is pushed, it is added to the min stack only if it is less than or equal to the current minimum; when popped, it is removed from the min stack if it matches the top. This ensures the top of the min stack always holds the current minimum without any traversal.

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AOTrust Uses x402 and NEAR Blockchain to Notarize AI Agent Outputs for $0.01

A new notarization service called AOTrust allows developers to cryptographically prove that an AI agent produced a specific output at a given point in time. The system works by hashing the agent's artifact and submitting it to an API that charges a flat fee of $0.01 in USDC via the x402 payment protocol on Base Layer 2. No account, API key, or signup is required — payment is handled inline through an HTTP 402 response cycle using EIP-3009 authorization. The service returns a 239-byte Provenance Data Record (PDR) signed with Ed25519, which is then anchored to the NEAR blockchain via a Merkle root for tamper-evident timestamping. The entire notarization process completes in two to five seconds, and the PDR can be verified independently without making any additional API calls.

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ProgrammingHacker News ·

Adrafinil keeps MacBooks awake with lid closed only while AI agents are running

A developer has released Adrafinil, a free open-source macOS utility designed to prevent MacBooks from sleeping when the lid is closed, but only while an AI coding agent is actively running. The tool was built in response to a common workaround where engineers kept their laptop lids partially open in public spaces to avoid sleep interrupting long-running AI agent tasks. Unlike always-on tools such as Amphetamine, Adrafinil uses hooks into tools like Claude Code and Codex to detect agent activity and automatically re-enables sleep once the agent finishes. It uses the macOS pmset command to toggle sleep blocking and includes safety measures such as allowing sleep if the device overheats. The app is fully notarized, MIT-licensed, and displays its active status in the menu bar.

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ProgrammingDEV Community ·

AI Coding Agents Create New Supply Chain Attack Surface, Researchers Warn

Security researchers have demonstrated that malicious code hidden in GitHub repositories can evade static scanners, human reviewers, and AI coding agents, activating only during routine project setup. The threat exploits a fundamental design trait of agentic tools: their ability to autonomously clone repositories and execute code without explicit human approval at each step. Unlike traditional supply chain attacks that required a developer to overlook something suspicious, this vector simply relies on the agent performing its intended function. The core concern is not that AI is being manipulated or jailbroken, but that automated pipelines are being granted unconditional trust without adequate sandboxing or permission controls. Security experts urge teams to treat any automated pipeline that clones and executes external code with the same scrutiny applied to arbitrary code execution.

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ProgrammingDEV Community ·

Docker Networking Explained: Bridge Networks, Host Mode, and Leaner Images

Docker assigns each container an IP address at creation, and by default uses a bridge network to enable host-to-container and container-to-container communication via port mapping. Unlike the default bridge network, a custom bridge network supports DNS-based name resolution, allowing containers to communicate using their names rather than IP addresses, which is better suited for production environments. Host network mode lets a container share the host's network stack directly without port mapping, though this is only fully supported on Linux. Port mapping with the -p flag remains the standard method for exposing containerized applications to the host machine. Multi-stage Docker builds help reduce final image size by copying only the necessary runtime artifacts, resulting in faster downloads, less storage use, and quicker container startup times.

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