42 lines
1.1 KiB
V
42 lines
1.1 KiB
V
module datatypes
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pub struct Queue<T> {
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mut:
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elements LinkedList<T>
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}
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// is_empty checks if the queue is empty
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pub fn (queue Queue<T>) is_empty() bool {
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return queue.elements.is_empty()
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}
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// len returns the length of the queue
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pub fn (queue Queue<T>) len() int {
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return queue.elements.len()
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}
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// peek returns the head of the queue (first element added)
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pub fn (queue Queue<T>) peek() ?T {
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return if !queue.is_empty() { queue.elements.first() ? } else { error('Queue is empty') }
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}
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// last returns the tail of the queue (last element added)
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pub fn (queue Queue<T>) last() ?T {
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return if !queue.is_empty() { queue.elements.last() ? } else { error('Queue is empty') }
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}
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// push adds an element to the tail of the queue
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pub fn (mut queue Queue<T>) push(item T) {
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queue.elements.push(item)
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}
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// pop removes the element at the head of the queue and returns it
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pub fn (mut queue Queue<T>) pop() ?T {
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return if !queue.is_empty() { queue.elements.shift() ? } else { error('Queue is empty') }
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}
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// str returns a string representation of the queue
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pub fn (queue Queue<T>) str() string {
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return queue.elements.str()
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}
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