[leetcode]219. Contains Duplicate II

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.

判断一个数组中有没有索引i，j，使nums[i]==nums[j]且，j-i<k

class Solution(object):
    def containsNearbyDuplicate(self, nums, k):
        d = collections.defaultdict(list)
        for i,c in enumerate(nums):
            if len(d[c])>0:
                l = i-max(d[c])
                if l<=k:
                    return True
            d[c].append(i)
        return False