Class: DLLModule::DLL
Overview
Class Doubly Linked List
Instance Attribute Summary collapse
- #size ⇒ Object readonly
Instance Method Summary collapse
-
#delete(value) ⇒ Object
Delete an specific element in DLL head.
-
#each ⇒ Object
Essential method for Enumerable.
-
#empty? ⇒ Boolean
Return if DLL is empty.
-
#extract_head ⇒ Node
Extract element in DLL head.
-
#extract_tail ⇒ Node
Extract element in DLL tail.
-
#get_head ⇒ head(#value)
Return head value.
-
#get_tail ⇒ tail(#value)
Return tail value.
-
#initialize(value = nil) ⇒ DLL
constructor
Constructor of DLL.
-
#insert_head(*value_array) ⇒ Object
Insert element in DLL head.
-
#insert_tail(*value_array) ⇒ Object
Insert element in DLL tail.
Constructor Details
Instance Attribute Details
#size ⇒ Object (readonly)
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# File 'lib/food/dll.rb', line 16 def size @size end |
Instance Method Details
#delete(value) ⇒ Object
Delete an specific element in DLL head
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# File 'lib/food/dll.rb', line 88 def delete (value) current_node = @head while !current_node.nil? if (current_node.value == value) if (@size == 1) @head = nil @tail = nil current_node = nil else if current_node != @head (current_node.prev).next = current_node.next end if current_node != @tail (current_node.next).prev = current_node.prev end current_node = nil end @size -= 1 else current_node = current_node.next end end end |
#each ⇒ Object
Essential method for Enumerable
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# File 'lib/food/dll.rb', line 131 def each current_node = @head while !current_node.nil? yield current_node.value current_node = current_node.next end end |
#empty? ⇒ Boolean
Return if DLL is empty
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# File 'lib/food/dll.rb', line 126 def empty? return size == 0 end |
#extract_head ⇒ Node
Extract element in DLL head
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# File 'lib/food/dll.rb', line 53 def extract_head if @head.nil? return nil else @size -= 1 node_to_return = @head @head = @head.next @head.prev = nil node_to_return.next = nil return node_to_return.value end end |
#extract_tail ⇒ Node
Extract element in DLL tail
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# File 'lib/food/dll.rb', line 71 def extract_tail if @tail.nil? return nil else @size -= 1 node_to_return = @tail @tail = @tail.prev @tail.next = nil node_to_return.prev = nil return node_to_return.value end end |
#get_head ⇒ head(#value)
Return head value
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# File 'lib/food/dll.rb', line 115 def get_head return @head.value end |
#get_tail ⇒ tail(#value)
Return tail value
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# File 'lib/food/dll.rb', line 121 def get_tail return @tail.value end |
#insert_head(*value_array) ⇒ Object
Insert element in DLL head
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# File 'lib/food/dll.rb', line 35 def insert_head (*value_array) value_array.each { |value| node = Node.new(value) insert_head_private(node); } end |
#insert_tail(*value_array) ⇒ Object
Insert element in DLL tail
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# File 'lib/food/dll.rb', line 44 def insert_tail (*value_array) value_array.each { |value| node = Node.new(value) insert_tail_private(node); } end |