Как решить с помощью Reduce?

Question

[be_a_man]

const arr = [[15], [25], [5], [20]].sort((a,b) => a[0]-b[0]).reduce(...)
// => [[0,5], [5, 20], [20, 40], [40, 65]]

Comments

[be_a_man]

TAbrahamyan, получить диапазоны https://jsfiddle.net/pjqtagx1/

Answer 1

[hzzzzl]

arr.reduce((acc, curr, i) => {
  const prev = i > 0 ? acc[i-1][1] : 0
  return [...acc, [prev, curr[0] + prev]]
}, [])

Answer 2

[0xD34F]

const result = [...arr]
  .sort((a, b) => a - b)
  .reduce((acc, n) => (acc[1].push([ acc[0], acc[0] += +n ]), acc), [ 0, [] ])
  .pop();