# 2006. Count Number of Pairs With Absolute Difference K
###### tags: `Leetcode` `Easy` `HashMap`
Link: https://leetcode.com/problems/count-number-of-pairs-with-absolute-difference-k/description/
## Code
```java=
class Solution {
public int countKDifference(int[] nums, int k) {
int ans = 0;
Map<Integer, Integer> cnt = new HashMap<>();
for(int num:nums){
ans += cnt.getOrDefault(num-k, 0)+cnt.getOrDefault(num+k, 0);
cnt.put(num, cnt.getOrDefault(num, 0)+1);
}
return ans;
}
}
```
```defaultdict()```括号里要设置默认值, 如果是int就会默认是0
```python=
class Solution:
def countKDifference(self, nums: List[int], k: int) -> int:
ans = 0
cnt = defaultdict(int)
for num in nums:
ans += cnt[num-k]+cnt[num+k]
cnt[num] += 1
return ans
```