2006. Count Number of Pairs With Absolute Difference K

Description

Given an integer array nums and an integer k, return the number of pairs (i, j) where i < j such that |nums[i] - nums[j]| == k.

The value of |x| is defined as:

• x if x >= 0.

• -x if x < 0.

Constraints

• 1 <= nums.length <= 200

• 1 <= nums[i] <= 100

• 1 <= k <= 99

Approach

Links

• Binarysearch

• GeeksforGeeks

• Leetcode

• ProgramCreek

• YouTube

Examples

Example 1

Input: nums = [1, 2, 2, 1], k = 1

Output: 4

Explanation: The pairs with an absolute difference of 1 are:

• [1, 2, 2, 1]

• [1, 2, 2, 1]

• [1, 2, 2, 1]

• [1, 2, 2, 1]

Example 2

Example 3

Solutions

Solution 1

/**
 * Time complexity : 
 * Space complexity : 
 */

class Solution {
    public int countKDifference(int[] nums, int k) {
        int n = nums.length, count = 0;
        
        for(int i = 0; i < n; i++) {
            for(int j = i+1; j < n; j++) {
                if(Math.abs(nums[i]-nums[j]) == k) {
                    count++;
                }
            }
        }
        
        return count;
    }
}

Solution 2

Follow up