3193. Count the Number of Inversions | Leetcode Contest 22 June 2024 | Hard | Dynamic Programming
"3193. Count the Number of Inversions" is a hard-level problem and the highest points-earning problem in the Bi-Weekly contest held on June 22, 2024, on LeetCode. The solution presented in the video is coded in Java, but the approach is explained using a dry-run on a whiteboard. This method makes the video accessible and beneficial for individuals with different programming backgrounds, as it focuses on the underlying logic rather than language-specific details.
Problem Intuition
The intuition behind this problem is somewhat akin to solving permutation-related problems on LeetCode, where the goal is to identify specific arrangements under certain conditions. In this case, we are tasked with counting the number of inversions in an array. An inversion occurs when a pair of elements is out of order, i.e., a larger element precedes a smaller one in the array.
Enhanced and Simplified Explanation
The challenge of counting inversions involves determining how many times a larger number appears before a smaller number in the array. This is a classic problem that can be approached using various methods, but understanding the fundamental intuition is key.
Understanding Inversions:
An inversion in an array A is a pair of indices (i, j) such that i is less than j and A[i] greater than A[j]. Essentially, we need to count these pairs to determine the number of inversions.
Intuitive Similarity to Permutations:
Just like in permutation problems where we explore different orderings, here we are interested in how elements can be arranged relative to each other to identify out-of-order pairs.
The concept of inversions is closely tied to the idea of sorting and ordering, making it reminiscent of permutation problems where order is key.
Link to the problem: https://leetcode.com/problems/count-t...
For doubts/queries, please reach out on [email protected]
Connect with me on Linkedin: / aditi-chourasia-a2a572121
Other problems for practice:
• 1052. Grumpy Bookstore Owner | Leetcode Da...
• 1552. Magnetic Force Between Two Balls | L...
• 826. Most Profit Assigning Work | Leetcode...
• 633. Sum of Square Numbers | Leetcode Dail...
• 502. IPO | Leetcode Daily Challenge ( POTD...
• 945. Minimum Increment to Make Array Uniqu...
• 2037. Minimum Number of Moves to Seat Ever...
• 1122. Relative Sort Array | Leetcode POTD ...
• 648. Replace Words | Leetcode POTD 7 June ...
#leetcodejava #leetcode #dailychallenge #potd #hindi