Arrays & Hashing/Easy

Contains DuplicatePRO PASS

Time: O(N)Space: O(N)

Initialize Hash Map

Target is 2. We iterate through nums array and maintain a hash map of { value: index }.

Array Elements & Pointers

i=0

i=1

i=2

i=3

Live Variables & Invariants

target:2

i:0

current:-

complement:-

Step 1 / 911%

Solution Code

function containsDuplicate(nums: number[]): boolean {

  const seen = new Set<number>();

  for (const num of nums) {

    if (seen.has(num)) return true;

    seen.add(num);

  return false;

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Array Input (comma separated):

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