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moriarty99779/gist:83880be8d00f6904318cf47deb02cab5

Created May 6, 2024 14:48
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PHP Find sum of all numbers from 1..N
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gistfile1.txt
function get_sum(int $n = 100) {
$sum = $n * ($n + 1) / 2;
return $sum;
}
@moriarty99779
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This is the basic algorithm that is often used to answer questions found on entry-level programming job interview questions. Basically, take the highest number $n, add one to it - $n + 1, multiply it by the original $n, then divide by 2.

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