Jens Neuhalfen

This & That

Random Ramblings about Life, the Universe, and Everything


LeetCode #10 : Regular Expression Matching

solution in python3: 44 ms, faster than 86.57%, Memory Usage: 12.7 MB, less than 100.00%

[Jens Neuhalfen]

10 minutes read

Given an input string (s) and a pattern (p), implement regular expression matching with support for . and *.

LeetCode #23 : Merge k Sorted Lists

$O(n * log(k))$ solution in python3: faster than 83.12%

[Jens Neuhalfen]

8 minutes read

Merge k sorted linked lists and return it as one sorted list. Analyze and describe its complexity.

LeetCode #1 : Two Sum

$O(n)$ solution in python3: 44 ms, faster than 97,63%

[Jens Neuhalfen]

8 minutes read

Given an array of integers, return indices of the two numbers such that they add up to a specific target.

LeetCode #2: Add Two Numbers

$O(n)$ solution in python3: 64 ms, faster than 93,77%

[Jens Neuhalfen]

3 minutes read

You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order and each of their nodes contain a single digit. Add the two numbers and return it as a linked list.

LeetCode #3: Longest Substring Without Repeating Characters

$O(n)$ solution in python3: 44 ms, faster than 99.09%

[Jens Neuhalfen]

5 minutes read

Given a string, find the length of the longest substring without repeating characters.

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Information security and software development are enablers for a successful company. During the last 20+ years of my working life I have always been convinced that outstanding success is only possible if everybody works together to find and reach a common goal.