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 difference between i and jis at most k.

 

和类似，多了个判断而已。

注意可能有多个重复，例如[1,0,1,1],1 为 True。

1 class Solution { 2 public: 3     bool containsNearbyDuplicate(vector
     
      & nums, int k) { 4         unordered_map
      
        showed; 5         for(int i=0;i