Contains Duplicate
Given an integer array nums, return true if some value appears at least twice, and false if every element is distinct.
Only the values matter, not their positions: [5, 1, 5] has a duplicate even though the two 5s are not neighbours.
Constraints
1 <= nums.length <= 10^5-10^9 <= nums[i] <= 10^9
Examples
Example 1
Input: nums = [1,2,3,1] Output: true
1 appears at index 0 and index 3.
Example 2
Input: nums = [1,2,3,4] Output: false
Every value is different.
Example 3
Input: nums = [4,4,4,4] Output: true
Only one distinct value, repeated: the first repeat is found at index 1.
JavaScript you'll use: Map and Set Arrays: create, read, update
/**
* @param {number[]} nums
* @return {boolean}
*/
function containsDuplicate(nums) {
}
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