rust / beginner
Snippet
Working with Vectors
Vectors (Vec<T>) are growable arrays provided by the standard library, unlike fixed-size arrays. They support dynamic resizing with push() and offer powerful iteration methods like map(), filter(), and sum(). The iter() method creates an iterator for safe read-only access.
snippet.rs
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fn main() {let mut numbers: Vec<i32> = Vec::new();numbers.push(1);numbers.push(2);numbers.push(3);let doubled: Vec<i32> = numbers.iter().map(|x| x * 2).collect();let sum: i32 = numbers.iter().sum();if let Some(first) = numbers.first() {println!("First number: {}", first);}for (index, num) in numbers.iter().enumerate() {println!("Index {}: {}", index, num);}}
Breakdown
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let mut numbers: Vec<i32> = Vec::new();
Creates a new empty vector with explicit type annotation
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.iter().map(|x| x * 2).collect()
Chains iterator methods to transform and collect results
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numbers.first()
Returns Some(value) or None if vector is empty