Projet Euler 1

combinedMultiplesApproach.js

//jshint esnext:true
/*
Multiples of 3 and 5 - Problem 1

If we list all the natural numbers below 10 that are multiples of 3 or 5, 
we get 3, 5, 6 and 9. The sum of these multiples is 23.

Find the sum of all the multiples of 3 or 5 below 1000.
*/

// getMultiples :: Integer -> Integer -> [Integer]
const getMultiples = R.curry((max, mult) => R.compose(R.map(R.multiply(mult)),
                                                      R.range(1))(parseInt(max / mult) + 1));

// sumOfMultiples :: Integer -> [Integer] -> Integer
const sumOfMultiples = max => R.compose(
                 R.sum,
                 R.uniq,
                 R.apply(R.concat),
                 R.map(getMultiples(max)));

console.log(sumOfMultiples(1000)([5,3]));

orPredicateApproach.js

//jshint esnext:true
/*
Multiples of 3 and 5 - Problem 1

If we list all the natural numbers below 10 that are multiples of 3 or 5, 
we get 3, 5, 6 and 9. The sum of these multiples is 23.

Find the sum of all the multiples of 3 or 5 below 1000.
*/

// isMultiple :: Integer -> (Integer -> Bool)
const isMultiple = mult => R.compose(R.equals(0), (R.modulo(R.__, mult)));

// multiplesCheck :: [Integer] -> (Integer -> Bool)
const multiplesCheck = R.compose(R.anyPass, R.map(isMultiple));

// sumOfMultiplesOr :: Integer -> [Integer] -> Integer
const sumOfMultiplesOr = max => multiples => R.compose(
                                R.sum,
                                R.filter(multiplesCheck(multiples)),
                                R.range(1))(max);

console.log(sumOfMultiplesOr(1000)([3, 5]))