LeetCode 217 - Contains Duplicate Problem

Problem Statement

Given an array of integers, find if the array contains any duplicates.

Your function should return true if any value appears at least twice in the array, and it should return false if every element is distinct.

Example 1:

Input: [1,2,3,1]
Output: true

Example 2:

Input: [1,2,3,4]
Output: false

Example 3:

Input: [1,1,1,3,3,4,3,2,4,2]
Output: true

Solution:

class Solution: def containsDuplicate(self, nums: List[int]) -> bool: if not nums: return False seen = {} for i in range(len(nums)): if nums[i] in seen: return True seen[nums[i]]=i return False