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.
solution:
hash表
code:
class Solution {
public:
bool containsNearbyDuplicate(vector<int>& nums, int k) {
unordered_map<int, int> hash;
for(int i = 0; i < nums.size(); i++)
{
if(i > k) hash[nums[i-k-1]]--;
if(hash[nums[i]] > 0) return true;
hash[nums[i]]++;
}
return false;
}
};