20 lines
564 B
Markdown
20 lines
564 B
Markdown
---
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title: isArmstrongNumber
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tags: math,beginner
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---
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Checks if the given number is an Armstrong number or not.
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Convert the given number into an array of digits. Use the exponent operator (`**`) to get the appropriate power for each digit and sum them up. If the sum is equal to the number itself, return `true` otherwise `false`.
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```js
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const isArmstrongNumber = digits =>
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(arr => arr.reduce((a, d) => a + parseInt(d) ** arr.length, 0) == digits)(
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(digits + '').split('')
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);
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```
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```js
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isArmstrongNumber(1634); // true
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isArmstrongNumber(56); // false
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``` |