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POHow to produce a random number sequence that doesn't produce more than X consecutive elements
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  1. POHow to produce a random number sequence that doesn't produce more than X consecutive elements
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    copied!<p>Ok, I really don't know how to frame the question properly because I barely have any idea how to describe what I want in one sentence and I apologize.</p> <p>Let me get straight to the point and you can just skip the rest cause I just want to show that I've tried something and not coming here to ask a question on a whim.</p> <p>I need an algorithm that produces 6 random numbers where it may not produce more than 2 consecutive numbers in that sequence.</p> <p>example: 3 3 4 4 2 1</p> <p>^FINE.</p> <p>example: 3 3 3 4 4 2</p> <p>^<strong>NO! <em>NO!</em></strong> WRONG!</p> <p>Obviously, I have no idea how to do this without tripping over myself constantly. </p> <p>Is there a STL or Boost feature that can do this? Or maybe someone here knows how to concoct an algorithm for it. That would be awesome.</p> <p><strong>What I'm trying to do and what I've tried.</strong>(the part you can skip)</p> <p>This is in C++. I'm trying to make a Panel de Pon/Tetris Attack/Puzzle League whatever clone for practice. The game has a 6 block row and 3 or more matching blocks will destroy the blocks. <a href="http://www.youtube.com/watch?v=zVKbhgQA3OY&amp;feature=related" rel="nofollow">Here's a video in case you're not familiar.</a></p> <p>When a new row comes from the bottom it must not come out with 3 horizontal matching blocks or else it will automatically disappear. Something I do not want for horizontal. Vertical is fine though.</p> <p>I've tried to accomplish just that and it appears I can't get it right. When I start the game chunks of blocks are missing because it detects a match when it shouldn't. My method is more than likely heavy handed and too convoluted as you'll see.</p> <pre><code>enum BlockType {EMPTY, STAR, UP_TRIANGLE, DOWN_TRIANGLE, CIRCLE, HEART, DIAMOND}; vector&lt;Block&gt; BlockField::ConstructRow() { vector&lt;Block&gt; row; int type = (rand() % 6)+1; for (int i=0;i&lt;6;i++) { row.push_back(Block(type)); type = (rand() % 6) +1; } // must be in order from last to first of the enumeration RowCheck(row, diamond_match); RowCheck(row, heart_match); RowCheck(row, circle_match); RowCheck(row, downtriangle_match); RowCheck(row, uptriangle_match); RowCheck(row, star_match); return row; } void BlockField::RowCheck(vector&lt;Block&gt; &amp;row, Block blockCheckArray[3]) { vector&lt;Block&gt;::iterator block1 = row.begin(); vector&lt;Block&gt;::iterator block2 = row.begin()+1; vector&lt;Block&gt;::iterator block3 = row.begin()+2; vector&lt;Block&gt;::iterator block4 = row.begin()+3; vector&lt;Block&gt;::iterator block5 = row.begin()+4; vector&lt;Block&gt;::iterator block6 = row.begin()+5; int bt1 = (*block1).BlockType(); int bt2 = (*block2).BlockType(); int bt3 = (*block3).BlockType(); int bt4 = (*block4).BlockType(); int type = 0; if (equal(block1, block4, blockCheckArray)) { type = bt1 - 1; if (type &lt;= 0) type = 6; (*block1).AssignBlockType(type); } else if (equal(block2, block5, blockCheckArray)) { type = bt2 - 1; if (type &lt;= 0) type = 6; (*block2).AssignBlockType(type); } else if (equal(block3, block6, blockCheckArray)) { type = bt3 - 1; if (type == bt3) type--; if (type &lt;= 0) type = 6; (*block3).AssignBlockType(type); } else if (equal(block4, row.end(), blockCheckArray)) { type = bt4 - 1; if (type == bt3) type--; if (type &lt;= 0) type = 6; (*block4).AssignBlockType(type); } } </code></pre> <p><em>Sigh</em>, I'm not sure if it helps to show this...At least it shows that I've tried something.</p> <p>Basically, I construct the row by assigning random block types, described by the BlockType enum, to a Block object's constructor(a Block object has blockType and a position). </p> <p>Then I use a RowCheck function to see if there's 3 consecutive blockTypes in one row and I have do this for all block types. The *_match variables are arrays of 3 Block objects with the same block type. If I do find that there are 3 consecutive block types then, I just simply subtract the first value by one. However if I do that I might end up inadvertently producing another 3 match so I just make sure the block types are going in order from greatest to least.</p> <p>Ok, it's crappy, it's convoluted and it doesn't work! That's why I need your help. </p>
 

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