title | tags |
---|---|
sumPower |
math,intermediate |
Returns the sum of the powers of all the numbers from start
to end
(both inclusive).
- Use
Array.prototype.fill()
to create an array of all the numbers in the target range,Array.prototype.map()
and the exponent operator (**
) to raise them topower
andArray.prototype.reduce()
to add them together. - Omit the second argument,
power
, to use a default power of2
. - Omit the third argument,
start
, to use a default starting value of1
.
const sumPower = (end, power = 2, start = 1) =>
Array(end + 1 - start)
.fill(0)
.map((x, i) => (i + start) ** power)
.reduce((a, b) => a + b, 0);
sumPower(10); // 385
sumPower(10, 3); // 3025
sumPower(10, 3, 5); // 2925