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POFinding the longest sequence on a board?
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copied!<p>I need a function that does the following:</p> <p>As input, it takes a n by n board, on which each spot is either empty, has a black stone or a white stone, and a position.</p> <p>As output, it returns the length of the longest sequence from the given position. If the position is empty, it returns 0.</p> <p>For example, if this board was inputted.</p> <pre><code>BUUUU WWWB UUUUU </code></pre> <p>where B is a black stone, W is a white stone and U is an empty spot, and the position inputted was (1,0), the output would 3.</p> <p>Or if this board was inputted:</p> <pre><code>BUUU WUUU BUUU BUUU </code></pre> <p>and the position was 0,3 the output would be zero, since the position is empty. If the position was 3,0 the output would be 2 because of the black column.</p> <p>Sequences can be horizontal, vertical or diagonal.</p> <p>This is what I have so far:</p> <p>If I'm given a position, I loop up, down, both sides, and both diagonals. I keep lopping until I find the sequence breaks, and then return the longest sequence. For example, if this is the board:</p> <pre><code>WUU WWU WUU </code></pre> <p>and the position was 1,0. I would loop sideways and find that the longest horizontal sequence is 1, loop diagonally, find the longest sequence is 1 and then loop vertically and find the longest sequence is 3, and therefore return 3.</p> <p>How can I do this faster? This function needs to be called around 10 million times in one second. My current function can execute around 8 million times per second.</p>

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