Maximum Difference Between Even and Odd Frequency II - Leetcode 3445
Quick explanation:
We explore every pair (a, b) to maximize freq[a] - freq[b].
We sliding-window the string of length ≥ k, keeping track of prefix counts and parity states.
For each valid window, the difference between current (cntA – cntB) and the smallest earlier (prevA – prevB) with flipped a-parity gives a candidate result.
We keep the global maximum across all pairs and windows.
This efficiently finds the maximum difference where a appears an odd number of times and b an even number, across all substrings of length at least k.
For the complexities:
Time Complexity: We have 25 pairs of (a, b), and each pair uses a sliding window across the string once, so O(25·n) = O(n)
Space Complexity: O(1) extra space (just counters, arrays of size 4, etc.)
Видео Maximum Difference Between Even and Odd Frequency II - Leetcode 3445 канала ThinkOutsideTheBox
We explore every pair (a, b) to maximize freq[a] - freq[b].
We sliding-window the string of length ≥ k, keeping track of prefix counts and parity states.
For each valid window, the difference between current (cntA – cntB) and the smallest earlier (prevA – prevB) with flipped a-parity gives a candidate result.
We keep the global maximum across all pairs and windows.
This efficiently finds the maximum difference where a appears an odd number of times and b an even number, across all substrings of length at least k.
For the complexities:
Time Complexity: We have 25 pairs of (a, b), and each pair uses a sliding window across the string once, so O(25·n) = O(n)
Space Complexity: O(1) extra space (just counters, arrays of size 4, etc.)
Видео Maximum Difference Between Even and Odd Frequency II - Leetcode 3445 канала ThinkOutsideTheBox
Комментарии отсутствуют
Информация о видео
11 июня 2025 г. 11:37:09
00:00:38
Другие видео канала
Lowest Common Ancestor Deepest Leaves - Leetcode 1123
Koko Eating Bananas - Leetcode (Python)
Minimum Cost to Make at Least One Valid Path in a Grid - Leetcode 1368
Minimum Cost Walk in Weighted Graph - Leetcode 3108
Binary Search Algorithm
Maximum Subarray - Python (Leetcode)
Maximum Width Ramp - Leetcode (Python)
Integer to Roman - Leetcode 12 (Python)
Divide Array Into Equal Pairs - Leetcode 2206
Leetcode 2490 - Circular Sentence (Python)
Minimum Number of Operations to Make Elements in Array Distinct - Leetcode 3396
Push Dominoes - Leetcode 838
Count Total Number of Colored Cells - Leetcode 2579
Divisible and Non-divisible Sums Difference - LeetCode 2894
Minimum Size Subarray Sum - LeetCode
Number of Ways to Split Array - Leetcode
Word Subsets - Leetcode 916
Making a Large Island - Leetcode 827
Random Password Generator (Python)
Number of Substrings Containing All Three Characters - Leetcode 1358
Length of Longest Fibonacci Subsequence - Leetcode 873
