gistfile1.js

function rMap(array, callback) {
// seu codigo
}
function rFilter(array, callback) {
// seu codigo
}
function rLength(array) {
  return array.length
}

const aa = [1,2,3,4]
console.log(rLength(aa))
let bb = rMap(aa, (element) => element + 1) 
console.log(bb)// [2,3,4,5]
bb = aa.map((element) => element + 1) 
console.log(bb)// [2,3,4,5]
bb = rFilter(aa, (element) => element > 2)
console.log(bb) // [3,4]
bb = aa.filter((element) => element > 2)
console.log(bb) // [3,4]