Backtracking has proven itself to be a universal algorithmic technique that can be applied while solving all kinds of computational problems, from the most primitive (such as counting all possible ...

You are given an array nums of positive integers and a positive integer k. A subset of nums is beautiful if it does not contain two integers with an absolute difference equal to k. Return the number ...

# [1994. The Number of Good Subsets](https://leetcode.com/problems/the-number-of-good-subsets) [中文文档](/solution/1900-1999/1994.The%20Number%20of%20Good ...