6.Sets and Booleans.ipynb

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        "# Set and Booleans\n",
        "\n",
        "There are two other object types in Python that we should quickly cover. Sets and Booleans. \n",
        "\n",
        "##Sets\n",
        "\n",
        "Sets are an unordered collection of *unique* elements. We can construct them by using the set() function. Let's go ahead and make a set to see how it works"
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        "x = set()"
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        "# We add to sets with the add() method\n",
        "x.add(1)"
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        "Note the curly brackets. This does not indicate a dictionary! Although you can draw analogies as a set being a dictionary with only keys.\n",
        "\n",
        "We know that a set has only unique entries. So what happens when we try to add something that is already in a set?"
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        "# Add a different element\n",
        "x.add(2)"
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        "# Try to add the same element\n",
        "x.add(1)"
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      "source": [
        "Notice how it won't place another 1 there. That's because a set is only concerned with unique elements! We can cast a list with multiple repeat elements to a set to get the unique elements. For example:"
      ]
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      "source": [
        "# Create a list with repeats\n",
        "l = [1,1,2,2,3,4,5,6,1,1]"
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      "source": [
        "# Cast as set to get unique values\n",
        "set(l)"
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      "source": [
        "## Booleans\n",
        "\n",
        "Python  comes with Booleans (with predefined True and False displays that are basically just the integers 1 and 0). It also has a placeholder object called None. Let's walk through a few quick examples of Booleans (we will dive deeper into them later in this course)."
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        "# Set object to be a boolean\n",
        "a = True"
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        "#Show\n",
        "a"
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        "We can also use comparison operators to create booleans. We will go over all the comparison operators later on in the course."
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        "# Output is boolean\n",
        "1 > 2"
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        "We can use None as a placeholder for an object that we don't want to reassign yet:"
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        "# None placeholder\n",
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      "source": [
        "Thats it! You should now have a basic understanding of Python objects and data structure types. Next, go ahead and do the assessment test!"
      ]
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      "source": [
        "## **Challenge Problems** \n",
        "## [Symmetric-Difference](https://www.hackerrank.com/challenges/symmetric-difference/problem) -> [Solution](https://www.hackerrank.com/challenges/symmetric-difference/editorial)\n",
        "\n",
        "## [Set .union() Operation](https://www.hackerrank.com/challenges/py-set-union/problem)  \n",
        "## [Set .intersection() Operation](https://www.hackerrank.com/challenges/py-set-intersection-operation/problem)  \n",
        "## [Set .difference() Operation](https://www.hackerrank.com/challenges/py-set-difference-operation/problem)  \n",
        "\n"
      ]
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