5/25 每日一題(重複的值,並且索引差小於k)

 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

class Solution:

    def containsNearbyDuplicate(self, nums: List[int], k: int) -> bool:

        nums_dict={} #使用這個字典紀錄重複的值和索引

        for n,i in enumerate(nums):

            if i in nums_dict and n - nums_dict[i] <= k:

                #如果符合 重複的值 且 索引值差小於等於k 回傳True

                return True

            nums_dict[i]=n #加入字典

        return False