Project Euler Solutions

Yet another Euler - this time in Javascript

Features all 2016 Javascript/ Node.js buzzwords:

• ES2015 (formerly ES6)

• functional

• immutable data

• lazy sequences

Solved so far:

• #1 (3 lines)

• #16 (5 lines)

• #19 (5 lines)

• #20 (3 + 5 lines)

• #48 (8 lines)

• #92 (4 + 7 lines)

Alternative implementations

Euler #92

// :: Number -> Number
// Slow: takes about 90 seconds on a 2013 MacBook Pro
const euler92_ = (n) => I.Range(1, n)
  .map((n) => I.Seq(squareDigitChain(n)).last())
  // 10 % faster, but mutation going on:
  // .map((n) => [...squareDigitChain(n)].pop())
  .filter((n) => n === 89)
  .count()