mirror of
https://github.com/TheAlgorithms/Ruby
synced 2024-12-27 21:58:57 +01:00
72 lines
998 B
Ruby
72 lines
998 B
Ruby
class CircularQueue
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def initialize(max_size)
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@max_size = max_size
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@queue = Array.new(max_size, nil)
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@front = 0
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@back = 0
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@size = 0
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end
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attr_accessor :front, :back, :size
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attr_reader :max_size, :queue
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def empty?
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size == 0
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end
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def peek
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return nil if empty?
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queue[front]
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end
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def add(x)
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raise "Queue is at max capacity" if size == max_size
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queue[back] = x
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@back = (back + 1) % max_size
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@size += 1
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end
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def pop
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raise "Queue is empty" if size == 0
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temp = queue[front]
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queue[front] = nil
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@front = (front + 1) % max_size
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@size -= 1
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temp
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end
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end
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queue = CircularQueue.new(3)
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begin
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queue.pop
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rescue => e
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puts e.message
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end
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queue.add(1)
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queue.add(2)
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queue.add(3)
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begin
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queue.add(4)
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rescue => e
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puts e.message
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end
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puts queue.inspect
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# => #<CircularQueue:0x00007fea23876cd8 @max_size=3, @queue=[1, 2, 3], @front=0, @back=0, @size=3>
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puts queue.peek
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# => 1
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queue.pop
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puts queue.peek
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# => 2
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