40 lines
1.0 KiB
Markdown
40 lines
1.0 KiB
Markdown
---
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title: Smallest multiple
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---
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## Problem 5: Smallest multiple
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### Method:
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- In this challenge we need to find the LCM of 1 to n numbers.
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- To find LCM of a number we use the following formula:
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- ![lcm](https://wikimedia.org/api/rest_v1/media/math/render/svg/9453a93953efe119b7502c1827aeeb869ab121d6)
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- To find GCD (Greatest Common Divisor) of two number we use Euclidean algorithm.
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- Once we get LCM of two numbers, we can get LCM of the numbers from 1 to n.
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### Solution:
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```js
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//LCM of two numbers
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function lcm(a, b){
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return (a*b)/gcd(a, b);
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}
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//Euclidean recursive algorithm
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function gcd(a, b){
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if (b === 0) return a;
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return gcd(b, a%b);
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}
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function smallestMult(n){
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let maxLCM = 1;
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//Getting the LCM in the range
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for (let i = 2; i <= n; i++){
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maxLCM = lcm(maxLCM, i);
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}
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return maxLCM;
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}
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```
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- [Run Code](https://repl.it/@ezioda004/Problem-5-Smallest-multiple)
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### References:
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- [Euclidean algorithm](https://en.wikipedia.org/wiki/Euclidean_algorithm)
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- [LCM](https://en.wikipedia.org/wiki/Least_common_multiple)
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