Author Archives: Hieu Nguyen

About Hieu Nguyen

I am a Senior member of technical staff (Oracle, eBay, Microsoft) and a founder of iNest, LLC (an IoT company)

System Design Tools and Templates

Posted on November 6, 2022 by Hieu Nguyen

Tools Draw.io Visual paradigm Lucid chart 2. Templates Problem Statement Scope Design Goals Assumptions High Level Design Challenges Open Items References

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Interview Resources

Posted on November 5, 2022 by Hieu Nguyen

Pramp BigOCheatSheet Hackerrank Interviewing.io Grokking the system design interview Cracking the coding interview Leetcode

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common git problems

Posted on November 5, 2022 by Hieu Nguyen

Delete the remote branch git push -d origin <branch_name> Delete the local branch git branch -D <branch_name> Merge master into feature branch git checkout master git pull git checkout feature git merge master Checkout from a specific commit Use git checkout … Continue reading →

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longest-substring-without-duplicate-characters

Posted on November 5, 2022 by Hieu Nguyen

public class LengthOfLongestSubstring { public static int lengthOfLongestSubstring(String s) { if (s == null) { return 0; } Map<Character, Integer> map = new HashMap<>(); int maxLength = 0; int start = 0; for (int i = 0; i < s.length(); … Continue reading →

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sorted-square

Posted on November 5, 2022 by Hieu Nguyen

public class SortedSquare { public static int[] sortedSquare(int[] nums) { int[] result = new int[nums.length]; int writeIndex = nums.length – 1; int l = 0, r = nums.length – 1; while (l <= r) { if (nums[l] * nums[l] < … Continue reading →

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sum-of-left-leaves

Posted on October 19, 2022 by Hieu Nguyen

package us.inest.app.dcp.recursion; import us.inest.app.dcp.tree.TreeNode; public class SumOfLeftLeaves { public static int sumOfLeftLeaves(TreeNode root) { // base case if (root == null) { return 0; } // left child is a leaf node if (root.left != null && root.left.left == null … Continue reading →

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remove-nth-node-from-end-of-list

Posted on October 18, 2022 by Hieu Nguyen

LeetCode link: https://leetcode.com/problems/remove-nth-node-from-end-of-list/submissions/684704570/ Java Solution

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