45 lines
1.4 KiB
Swift
45 lines
1.4 KiB
Swift
/**
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* File: deque.swift
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* Created Time: 2023-01-14
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* Author: nuomi1 (nuomi1@qq.com)
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*/
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@main
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enum Deque {
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/* Driver Code */
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static func main() {
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/* Initialize double-ended queue */
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// Swift does not have a built-in double-ended queue class, Array can be used as a double-ended queue
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var deque: [Int] = []
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/* Element enqueue */
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deque.append(2)
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deque.append(5)
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deque.append(4)
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deque.insert(3, at: 0)
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deque.insert(1, at: 0)
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print("Double-ended queue deque = \(deque)")
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/* Access element */
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let peekFirst = deque.first!
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print("Front element peekFirst = \(peekFirst)")
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let peekLast = deque.last!
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print("Back element peekLast = \(peekLast)")
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/* Element dequeue */
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// When simulating with Array, complexity of popFirst is O(n)
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let popFirst = deque.removeFirst()
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print("Front dequeued element popFirst = \(popFirst), deque after front dequeue = \(deque)")
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let popLast = deque.removeLast()
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print("Back dequeued element popLast = \(popLast), deque after back dequeue = \(deque)")
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/* Get the length of the double-ended queue */
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let size = deque.count
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print("Double-ended queue length size = \(size)")
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/* Determine if the double-ended queue is empty */
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let isEmpty = deque.isEmpty
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print("Is the double-ended queue empty = \(isEmpty)")
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}
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}
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