Class: DS::Stack

Inherits:
Object
  • Object
show all
Defined in:
lib/ds/stacks/stack.rb

Overview

Class implements Stack data structure. Internaly uses array to store elements.

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Stack

Returns a new instance of Stack.



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# File 'lib/ds/stacks/stack.rb', line 8

def initialize
  @store = []
end

Instance Method Details

#empty? ⇒ Boolean

If stack is empty returns true otherwise returns false.

Returns:

  • (Boolean) 


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# File 'lib/ds/stacks/stack.rb', line 33

def empty?
  @store.empty?
end

#peek ⇒ Object

Returns element from the top of the stack.



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# File 'lib/ds/stacks/stack.rb', line 28

def peek
  @store.last
end

#pop ⇒ Object

Removes element from stack and returns it.



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# File 'lib/ds/stacks/stack.rb', line 18

def pop
  @store.pop
end

#push(x) ⇒ Object

Adds element to the top of the stack.



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# File 'lib/ds/stacks/stack.rb', line 23

def push(x)
  @store.push x
end

#size ⇒ Object

Returns the stack size.



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# File 'lib/ds/stacks/stack.rb', line 13

def size
  @store.size
end