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POChris Pine Ruby ch 10, recursion
 

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    <p>I have been trying to learn ruby using the book 'learn to program' by Chris Pine. I was actually getting excited when going through the book until I got to chapter 10 and the examples used. Now this chapter alone and its examples have completely deflated all of my excitement to continue with this book. In this example I have completely no idea how its trying to count the tiles, or why he uses world [y],[x] when the method was defined with the attribute of continent_size world, x,y? Im not sure how the recursion in this example works. Can someone shed some more light onto this example as to what the author was actually trying to do?</p> <pre><code>M = 'land' o = 'water' world = [ [o,o,o,o,o,M,o,o,o,o,o], [o,o,o,o,M,M,o,o,o,o,o], [o,o,o,o,o,M,o,o,M,M,o], [o,o,o,M,o,M,o,o,o,M,o], [o,o,o,o,o,M,M,o,o,o,o], [o,o,o,o,M,M,M,M,o,o,o], [M,M,M,M,M,M,M,M,M,M,M], [o,o,o,M,M,o,M,M,M,o,o], [o,o,o,o,o,o,M,M,o,o,o], [o,M,o,o,o,M,M,o,o,o,o], [o,o,o,o,o,M,o,o,o,o,o]] def continent_size world, x ,y if x &lt; 0 or x &gt; 10 or y &lt; 0 or y &gt; 10 return 0 end if world[y][x] != 'land' return 0 end size = 1 world [y][x] = 'counted land' size = size + continent_size(world, x-1, y-1) size = size + continent_size(world, x , y-1) size = size + continent_size(world, x+1, y-1) size = size + continent_size(world, x-1, y ) size = size + continent_size(world, x+1, y ) size = size + continent_size(world, x-1, y+1) size = size + continent_size(world, x , y+1) size = size + continent_size(world, x+1, y+1) size end puts continent_size(world, 5, 5) </code></pre>
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    1. COThis program and chapter is just not clicking. I feel like i get a grasp on recursion but then look at this code and get confused and frustrated. Can someone walk me through the code and explain what is happening?
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