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@@ -33,6 +33,7 @@ Some are in Jupyter (IPython) notebooks, some in `.py` files. You can view the f
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 |[When is Cheryl's Birthday?](ipynb/Cheryl.ipynb)&nbsp; &nbsp; **[NB](http:/nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Cheryl.ipynb)**, **[DN](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FCheryl.ipynb)**<br>*Solving the "Cheryl's Birthday" logic puzzle.*|
 |[When Cheryl Met Eve: A Birthday Story](ipynb/Cheryl-and-Eve.ipynb)&nbsp; &nbsp; **[NB](http:/nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Cheryl-and-Eve.ipynb)**, **[DN](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FCheryl-and-Eve.ipynb)**<br>*Inventing new puzzles in the Style of Cheryl's Birthday.*|
+|[How Many Soldiers Do You Need to Beat the Night King?](ipynb/NightKing.ipynb) **[NB](http:/nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/NightKing.ipynb)**, **[DN](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FNightKing.ipynb)**<br>*Investigasting a battle between the army of the dead and the army of the living.*|
 |[The Devil and the Coin Flip Game](ipynb/Coin%20Flip.ipynb)&nbsp; &nbsp; **[NB](http:/nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Coin%20Flip.ipynb)**, **[DN](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FCoin%2520Flip.ipynb)**<br>*How to beat the Devil at his own game.*|
 |[The Puzzle of the Misanthropic Neighbors](ipynb/Mean%20Misanthrope%20Density.ipynb)&nbsp; &nbsp; **[NB](http:/nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Mean%20Misanthrope%20Density.ipynb)**, **[DN](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FMean%2520Misanthrope%2520Density.ipynb)**<br>*How crowded will this neighborhood be, if nobody wants to live next door to anyone else?*|
 |[Four 4s, Five 5s, and Countdown to 2016](ipynb/Countdown.ipynb)&nbsp; &nbsp; **[NB](http:/nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Countdown.ipynb)**, **[DN](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FCountdown.ipynb)**<br>*Solving the equation 10 _ 9 _ 8 _ 7 _ 6 _ 5 _ 4 _ 3 _ 2 _ 1 = 2016. From an Alex Bellos puzzle.*|