Leaves - Mariya

lib/queue.rb

@@ -1,31 +1,57 @@
 class Queue
-
+  
   def initialize
     # @store = ...
-    raise NotImplementedError, "Not yet implemented"
+    @store = Array.new(10)
+    @front = -1
+    @back = -1
   end
-
+  
   def enqueue(element)
-    raise NotImplementedError, "Not yet implemented"
+    if @front == -1 && @back == -1
+      @front = 0
+      @back = 0 
+    end
+
+    if @front == @back && @store.compact.length > 0
+      front_array = @store.slice(0, @front)
+      back_array = @store.slice(@back, @store.length - 1)
+      @store = front_array + Array.new(10) + back_array
+      @front = (@front + 10) % @store.length
+    end
+
+    @store[@back] = element
+    @back = (@back + 1) % @store.length
   end
-
+  
   def dequeue
-    raise NotImplementedError, "Not yet implemented"
+    removed = @store[@front]
+    @store[@front] = nil 
+    @front = (@front + 1) % @store.length 
+    return removed
   end
-
+  
   def front
-    raise NotImplementedError, "Not yet implemented"
+    return @store[@front]
   end
-
+  
   def size
-    raise NotImplementedError, "Not yet implemented"
+    return @store.length
   end
-
+  
   def empty?
-    raise NotImplementedError, "Not yet implemented"
+    if @front == @back 
+      return true 
+    else 
+      return false 
+    end
   end
-
+  
   def to_s
-    return @store.to_s
+    if @front >= @back 
+      return (@store[@front..-1] + @store[0...@back]).to_s
+    else 
+      return @store[@front...@back].to_s
+    end
   end
 end

lib/stack.rb

@@ -1,21 +1,24 @@
+require_relative './linked_list'
+
 class Stack
   def initialize
     # @store = ...
-    raise NotImplementedError, "Not yet implemented"
+    @store = LinkedList.new
   end
-
+  
   def push(element)
-    raise NotImplementedError, "Not yet implemented"
+    # add to end of linked list
+    @store.add_last(element)
   end
-
+  
   def pop
-    raise NotImplementedError, "Not yet implemented"
+    @store.remove_last
   end
-
+  
   def empty?
-    raise NotImplementedError, "Not yet implemented"
+    @store.empty?
   end
-
+  
   def to_s
     return @store.to_s
   end

test/queue_test.rb

@@ -9,40 +9,35 @@
     q = Queue.new
     q.class.must_equal Queue
   end
-
+  
   it "adds something to an empty Queue" do
-    skip
     q = Queue.new
     q.enqueue(10)
     q.to_s.must_equal "[10]"
   end
-
+  
   it "adds multiple somethings to a Queue" do
-    skip
     q = Queue.new
     q.enqueue(10)
     q.enqueue(20)
     q.enqueue(30)
     q.to_s.must_equal "[10, 20, 30]"
   end
-
+  
   it "starts the size of a Queue at 0" do
-    skip
     q = Queue.new
     q.empty?.must_equal true
   end
-
+  
   it "removes something from the Queue" do
-    skip
     q = Queue.new
     q.enqueue(5)
     removed = q.dequeue
     removed.must_equal 5
     q.empty?.must_equal true
   end
-
+  
   it "removes the right something (LIFO)" do
-    skip
     q = Queue.new
     q.enqueue(5)
     q.enqueue(3)
@@ -51,9 +46,8 @@
     removed.must_equal 5
     q.to_s.must_equal "[3, 7]"
   end
-
+  
   it "properly adjusts the size with enqueueing and dequeueing" do
-    skip
     q = Queue.new
     q.empty?.must_equal true
     q.enqueue(-1)
@@ -63,16 +57,16 @@
     q.dequeue
     q.empty?.must_equal true
   end
-
+  
   it "returns the front element in the Queue" do
-    skip
     q = Queue.new
     q.enqueue(40)
     q.enqueue(22)
     q.enqueue(3)
     q.dequeue
     expect(q.dequeue).must_equal 22
   end
+
   it "works for a large Queue" do
     q = Queue.new
     q.enqueue(10)
@@ -92,15 +86,14 @@
     q.enqueue(130)
     q.enqueue(140)
     q.enqueue(150)
-    q.enqueue(150)
     q.enqueue(160)
     q.enqueue(170)
     q.enqueue(180)
     q.enqueue(190)
     q.enqueue(200)
     q.enqueue(210)
     q.dequeue
-
-    expect(q.to_s).must_equal('[40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240]')
+    
+    expect(q.to_s).must_equal('[40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210]')
   end
 end

test/stack_test.rb

@@ -8,40 +8,35 @@
     s = Stack.new
     s.class.must_equal Stack
   end
-
+  
   it "pushes something onto a empty Stack" do
-    skip
     s = Stack.new
     s.push(10)
     s.to_s.must_equal "[10]"
   end
-
+  
   it "pushes multiple somethings onto a Stack" do
-    skip
     s = Stack.new
     s.push(10)
     s.push(20)
     s.push(30)
     s.to_s.must_equal "[10, 20, 30]"
   end
-
+  
   it "starts the stack empty" do
-    skip
     s = Stack.new
     s.empty?.must_equal true
   end
-
+  
   it "removes something from the stack" do
-    skip
     s = Stack.new
     s.push(5)
     removed = s.pop
     removed.must_equal 5
     s.empty?.must_equal true
   end
-
+  
   it "removes the right something (LIFO)" do
-    skip
     s = Stack.new
     s.push(5)
     s.push(3)