LeetCode 219 Contains Duplicate II - Easy

219. Contains Duplicate II — Easy

Open on LeetCode

Problem

219. Contains Duplicate II -- Easy

Given an array of integers and an integer k, find out whether there are two distinct indices i and j in the array such that nums[i] = nums[j] and the absolute difference between i and j is at most 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

Solution

class Solution:
    def containsNearbyDuplicate(self, nums: List[int], k: int) -> bool:
        map = dict()
        for i, v in enumerate(nums):
            if v not in map:
                map[v] = i
            else:
                diff = i - map[v]
                map[v] = i
                if diff <= k:
                    return True
        return False