Contains Duplicate II

题目：

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

解法：

class Solution:

# @param {integer[]} nums

# @param {integer} k

# @return {boolean}

def containsNearbyDuplicate(self, nums, k):

sorted_nums = nums[:]

sorted_nums.sort()

if len(nums)<=1:

return False

for index,value in enumerate(sorted_nums):

if index<len(sorted_nums)-1 and value==sorted_nums[index+1]:

index1 = nums.index(value)

nums.remove(value)

index2 = nums.index(value)+1

if index2-index1<=k:

return True

return False