Chapter 9 Quiz.ipynb

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    "1. How are Python dictionaries different from Python lists?\n",
    "    - Python lists are indexed using integers and dictionaries can use strings as indexes\n",
    "2. What is a term commonly used to describe the Python dictionary feature in other programming languages?\n",
    "    - Associative arrays\n",
    "3. What would the following Python code print out? stuff = dict(); print stuff['candy']\n",
    "    - The program would fail with a traceback\n",
    "4. What would the following Python code print out? stuff = dict(); print stuff.get('candy',-1)\n",
    "    - -1\n",
    "5. (T/F) When you add items to a dictionary they remain in the order in which you added them.\n",
    "    - False\n",
    "6. What is a common use of Python dictionaries in a program?\n",
    "    - Building a histogram counting the occurrences of various strings in a file\n",
    "7. Which of the following lines of Python is equivalent to the following sequence of statements assuming that counts is a dictionary? if key in counts: counts[key] = counts[key] + 1 else: counts[key] = 1\n",
    "    - counts[key] = counts.get(key,0) + 1\n",
    "8. In the following Python, what does the for loop iterate through? x = dict() ... for y in x : ...\n",
    "    - It loops through the keys in the dictionary\n",
    "9. Which method in a dictionary object gives you a list of the values in the dictionary?\n",
    "    - values()\n",
    "10. What is the purpose of the second parameter of the get() method for Python dictionaries?\n",
    "    - To provide a default value if the key is not found"
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