AD4. Queue.ipynb

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   "source": [
    "## Queue"
   ]
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  {
   "cell_type": "markdown",
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   "source": [
    "A Queue is a linear structure which follows a particular order in which the operations are performed. The order is **First In First Out (FIFO)**. A good example of a queue is any queue of consumers for a resource where the consumer that came first is served first. The difference between stacks and queues is in removing. In a stack we remove the item the most recently added; in a queue, we remove the item the least recently added.[Source](https://www.geeksforgeeks.org/queue-data-structure/)"
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   "source": [
    "class Queue:\n",
    "    def __init__(self, head=None):\n",
    "        self.storage = [head]\n",
    "\n",
    "    def enqueue(self, new_element):\n",
    "        self.storage.append(new_element)\n",
    "\n",
    "    def peek(self):\n",
    "        return self.storage[0]\n",
    "\n",
    "    def dequeue(self):\n",
    "        return self.storage.pop(0)\n"
   ]
  },
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   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### Set up"
   ]
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   "source": [
    "# Setup\n",
    "q = Queue(10)\n",
    "q.enqueue(20)\n",
    "q.enqueue(300)"
   ]
  },
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   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### Test peek"
   ]
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   "metadata": {},
   "outputs": [
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     "text": [
      "10\n"
     ]
    }
   ],
   "source": [
    "# Should be 1\n",
    "print(q.peek())"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### Test dequeue"
   ]
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   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
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     "text": [
      "10\n"
     ]
    }
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   "source": [
    "# Should be 1\n",
    "print(q.dequeue())"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### Test enqueue"
   ]
  },
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   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "20\n",
      "300\n",
      "4\n",
      "5\n"
     ]
    }
   ],
   "source": [
    "q.enqueue(4)\n",
    "# Should be 2\n",
    "print(q.dequeue())\n",
    "# Should be 3\n",
    "print(q.dequeue())\n",
    "# Should be 4\n",
    "print(q.dequeue())\n",
    "q.enqueue(5)\n",
    "# Should be 5\n",
    "print(q.peek())\n"
   ]
  },
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   "execution_count": null,
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   "outputs": [],
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   "execution_count": null,
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