23 lines
539 B
Markdown
23 lines
539 B
Markdown
---
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title: lcm
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tags: math,algorithm,recursion,intermediate
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---
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Calculates the least common multiple of two or more numbers.
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- Use the greatest common divisor (GCD) formula and the fact that `lcm(x, y) = x * y / gcd(x, y)` to determine the least common multiple.
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- The GCD formula uses recursion.
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```js
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const lcm = (...arr) => {
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const gcd = (x, y) => (!y ? x : gcd(y, x % y));
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const _lcm = (x, y) => (x * y) / gcd(x, y);
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return [...arr].reduce((a, b) => _lcm(a, b));
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};
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```
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```js
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lcm(12, 7); // 84
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lcm(...[1, 3, 4, 5]); // 60
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```
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