LC 219 Contains Duplicate Ii

Implementation

// 219. Contains Duplicate II

// Given an integer array nums and an integer k, return true if there are two distinct indices i and j in the array such that nums[i] == nums[j] and abs(i - j) <= k.

// Example 1:
// Input: nums = [1,2,3,1], k = 3
// Output: true

// Example 2:
// Input: nums = [1,0,1,1], k = 1
// Output: true

// Example 3:
// Input: nums = [1,2,3,1,2,3], k = 2
// Output: false
 

// Constraints:
// 1 <= nums.length <= 105
// -109 <= nums[i] <= 109
// 0 <= k <= 105

// optimize solution
const containsDuplicate = (nums,k) => {
    if (k <= 0) return false;
    const s = new Map();
    for(let i=0;i<nums.length;i++){
        if(s.has(nums[i])) {
            const temp = Math.abs(s.get(nums[i])-i);
            if(temp<=k) return true;
        }
        s.set(nums[i],i);
    }
    return false;
};

console.log(containsDuplicate([1,2,3,1],3))
console.log(containsDuplicate([1,0,1,1],1))
console.log(containsDuplicate([1,2,3,1,2,3],2))

export { containsDuplicate };

Tests

// Test stub for 03.219.ContainsDuplicateII

describe('03.219.ContainsDuplicateII', () => {
  it('should have a test stub', () => {
    expect(true).toBe(true);
  });
});