15 lines
437 B
JavaScript
15 lines
437 B
JavaScript
// where tl and br are the top left and bottom right cell respectively
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function countSquares(tl, br) {
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// these are the four cells to interrogate
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let topLeft, left, top, whole;
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// 1d index = x + #rows * y
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topLeft = t[(tl.x - 1) + n * (tl.y - 1)].count;
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left = t[(tl.x - 1) + n * bry].count;
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top = t[br.x + n * (tl.y - 1)].count;
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whole = t[br.x + n * br.y].count;
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return whole + topLeft - top - left;
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}
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