3. Contains Duplicate

Given an integer array nums, return true if any value appears at least twice in the array, and return false if every element is distinct.


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

Example 2:
Input: nums = [1,2,3,4]
Output: false

Example 3:
Input: nums = [1,1,1,3,3,4,3,2,4,2]
Output: true


The most pythonic way to solve this question is by using the power of set.

def containsDuplicate(nums):
    if len(set(nums)) == len(nums):
        return False
    else:
        return True

If you are in a mood of further reducing the number of lines of code, here another way to do it.

def containsDuplicate(nums):
  return len(nums) != len(set(nums))