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 HTC Worst Warranty or Customer Service Ever September 21, 2015
 My first day at work April 10, 2014
 “Not having enough time”, really? March 30, 2014
 Triangle March 13, 2014
 Sum Root to Leaf Numbers March 13, 2014
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Monthly Archives: March 2014
“Not having enough time”, really?
How do you explain your failure? I always blame myself first, others later if any. However, I have come to realize that the most common reason people use to explain their failures is the lack of time. I do not … Continue reading
Posted in Life
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Triangle
http://oj.leetcode.com/problems/triangle/ The problem statement is deceptive by mentioning path from “top” to “bottom”. I was fooled at first and tried to compare all the ways from the top to the bottoms. However, it is impractical since there are O(2^(n1)) such … Continue reading
Posted in Computer Science, LeetCode
Tagged algorithm, dynamic programming, leetcode, recursion
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Sum Root to Leaf Numbers
http://oj.leetcode.com/problems/sumroottoleafnumbers/ Another problem from Leetcode that I came up with two different solutions. The first solution idea is to get paths from root to leaves first, compute the sum later. Those paths can be easily discovered by depth first search, … Continue reading
Posted in Computer Science, LeetCode
Tagged algorithm, interview, leetcode, question, tree
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Flatten Binary Tree
LeetCodeLink I have solved this problem weeks ago, but today I completely forgot how I had solved it. As I tried to simulate the interview, I started to think and finally came up with a solution, which is interestingly different … Continue reading
Posted in Computer Science, LeetCode
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BellmanFord’s Algorithm
Dijkstra’s algorithm is fast, but limited to nonnegatively weighted graph. It also does not applicable for distributed system. BellmanFord’s algorithm is the solution for the two problems. It is asymptotically slower than Dijkstra’s algorithm as its complexity is O(EV). However, … Continue reading
Posted in Algorithms, Computer Science
Tagged bellman, dijkstra, ford, graph, shortest
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Dijkstra’s Algorithm
2014/3/5: How stupid I was for not recognizing Dijkstra as a special case of A* without heuristic cost. It makes the algorithm much easier to understand and implement. We only need to consider vertices as states and put them to … Continue reading
Posted in Algorithms, Computer Science
Tagged algorithm, c++, dijkstra, graph, programming, shortest
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Max points on a line
I have been preparing for the coming technical interview for two weeks and Leetcode is my main source for practicing. I already solved over 80% problems, but I find it difficult to review my solution by merely looking at the … Continue reading