20 lines
674 B
Markdown
20 lines
674 B
Markdown
### sumPower
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Returns the sum of the powers of all the numbers from `start` to `end`.
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Use `Array.fill()` to create an array of all the numbers in the target range, `Array.map()` and the exponent operator (`**`) to raise them to `power` and `Array.reduce()` to add them together.
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Omit the second argument, `power`, to use a default power of `2`.
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Omit the third argument, `start`, to use a default starting value of `1`.
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```js
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const sumPower = (end,power = 2,start = 1) =>
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Array(end - start).fill(0).map((x,i) => (i+start) ** power).reduce((a,b) => a+b,0)
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```
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```js
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sumPower(10); // 385
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sumPower(10,3); //3025
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sumPower(10,3,5); //2925
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sumPower(10,undefined,5); //355
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```
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