duplicates-test.js

const nums = []

for (let i = 0; i <= 10000; i++) {
  nums.push(i)
}

const nums2 = [...nums, 10000]

// previously written functions for duplicates
// duplicates2, duplicates3, duplicates4

console.time('one')
duplicates(nums)
duplicates(nums2)
console.timeEnd('one') // one: 882.761ms

console.time('two')
duplicates2(nums)
duplicates2(nums2)
console.timeEnd('two') // two: 547.069ms

console.time('three')
duplicates3(nums)
duplicates3(nums2)
console.timeEnd('three') // three: 496.417ms

console.time('four')
duplicates4(nums)
duplicates4(nums2)
console.timeEnd('four') // four: 2.152ms