Vec, HashMap, String, iterator adapters, closures, Fn traits and smart pointers like Box, Rc and RefCell.
40 cards · basic cards · AI-written, checked twice. Edit anything.
- What does Vec do in Rust?
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A growable, heap-allocated array type with dynamic length- How do you create an empty Vec?
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Vec::new() or the vec![] macro- What does Vec::with_capacity(n) do?
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Allocates space for n elements without growing, starting empty- What does Vec::push() do?
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Adds an element to the end of the Vec- What does Vec::pop() return?
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Option<T>: Some(value) if Vec is not empty, None otherwise- What happens when you access Vec[out_of_bounds]?
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The program panics- What does Vec::get(index) return for a valid index?
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Some(&element)- What does .iter() on a Vec return?
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An iterator over immutable references to elements- What does .iter_mut() on a Vec return?
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An iterator over mutable references to elements- What does .into_iter() on a Vec do?
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Takes ownership and returns an iterator of moved values- What does HashMap provide?
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A collection of key-value pairs with O(1) average lookup time- How do you create a HashMap?
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HashMap::new() or collect() on an iterator of pairs- How do you insert a value into a HashMap?
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hashmap.insert(key, value)- How do you retrieve a value from a HashMap?
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hashmap.get(&key) returns Option<&V>- What does HashMap's Entry API do?
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Provides efficient access to insert a value only if the key is absent
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