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Computer Fundamentals → Introduction to Computer 38

Model checking in formal verification?
Exhaustively explores state space to verify temporal logic properties
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Hoare triple {P} C {Q} means?
If precondition P holds before C executes, postcondition Q holds after
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Invariant in programming is?
A condition that remains true throughout program execution
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Loop invariant is used to prove?
Loop correctness — condition true before, during, and after each iteration
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Decidability in computation theory means?
There exists an algorithm that always terminates with correct yes/no answer
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The Halting Problem is?
Undecidable — no algorithm can determine if arbitrary program halts
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Church-Turing thesis states?
Any effectively computable function is computable by a Turing machine
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Lambda calculus was developed by?
Alonzo Church — foundation of functional programming
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Automata theory studies?
Abstract mathematical machines and their computational power
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Regular language is recognized by?
Finite automaton (DFA/NFA)
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Context-free language is recognized by?
Pushdown automaton (PDA)
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Which language is context-sensitive but not context-free?
a^n b^n c^n
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Pumping lemma is used to prove?
A language is NOT regular (or not context-free)
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Type 0 grammar in Chomsky hierarchy generates?
Recursively enumerable languages (most general)
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Turing complete means?
Can simulate any Turing machine — compute any computable function
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von Neumann architecture is Turing complete because?
It can simulate any Turing machine computation with sufficient memory
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Which programming language paradigm models programs as mathematical functions?
Functional (Haskell, Erlang, Clojure)
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Logic programming (Prolog) uses?
Facts, rules, and queries — computation as logical inference
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Reactive programming is based on?
Asynchronous data streams and propagation of change
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Actor model of concurrency uses?
Independent actors communicating via message passing (no shared state)
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CSP (Communicating Sequential Processes) by Tony Hoare?
Formal model of concurrent processes communicating via channels
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Goroutines in Go language are?
Lightweight user-space threads managed by Go runtime with channels for communication
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async/await in Python is based on?
Coroutines and event loop — cooperative multitasking
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Event loop in Node.js/JavaScript?
Single-threaded non-blocking I/O through callback/promise/async-await mechanism
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libuv library provides Node.js with?
Cross-platform asynchronous I/O and event loop
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V8 JavaScript engine is developed by?
Google — also used in Node.js
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JIT (Just-In-Time) compilation?
Compiles frequently executed code at runtime to machine code
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Garbage collection (GC) in managed languages?
Automatically reclaims unused memory
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Mark-and-sweep GC algorithm?
Marks reachable objects, sweeps (frees) unmarked objects
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Reference counting GC fails with?
Circular references — objects referencing each other never reach count zero
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Generational GC is based on the observation that?
Most objects die young — frequent minor GC of young generation, rare major GC
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Concurrent GC (like Go's GC) runs?
Concurrently with the application, minimizing stop-the-world pauses
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LLVM is?
Compiler infrastructure providing reusable compiler and toolchain components
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Clang is?
C/C++/Objective-C compiler using LLVM backend
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Rust programming language is notable for?
Memory safety without GC using ownership/borrowing system
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Rust's ownership system ensures?
At most one mutable reference OR multiple immutable references at any time — preventing data races
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WebAssembly (WASM) is?
Binary instruction format for stack-based VM running in browsers at near-native speed
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Microarchitecture simulator is used for?
Modeling CPU behavior cycle-accurately for architectural research
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Computer Fundamentals → Memory Units 2

Chomsky hierarchy levels from most to least restricted?
Regular < Context-free < Context-sensitive < Recursively enumerable
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Coroutine differs from thread in?
Cooperative scheduling — yields control explicitly vs preemptive thread scheduling
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