Posts | Marc Lester Tan

Presentations (2)

Presentation (1)

Posts

158 posts

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Shortest Distance to a Character

Aug 23, 2019
One minute read

Here’s another tricky easy LC problem. ...

Matrix Cells in Distance Order

Aug 23, 2019
2 minutes read

To solve this easy LC problem, my initial idea was to use a TreeMap<Int, Pair<Int, Int>> to store the distance and its corresponding coordinate. TreeMap automatically sorts the keys during insertion so that will save us some time instead of sorting the keys ourselves. ...

Leaf Similar Trees

Aug 22, 2019
One minute read

This problem can be easily solved using recursive way. ...

First Bad Version

Aug 20, 2019
One minute read

This easy LC problem was asked in one of my past interviews (Facebook) which I think I didn’t really answered very well. ...

Maximum Depth of Binary Tree

Aug 20, 2019
One minute read

Another tree traversal easy LC problem. ...

Smallest Range I

Aug 20, 2019
One minute read

Here’s another short answer for an easy LC problem. ...

Reverse Words in a String III

Aug 19, 2019
One minute read

I solved this easy LC problem in less than 10 seconds :D ...

Middle of the Linked List

Aug 19, 2019
2 minutes read

My first solution for this easy LC problem involves traversing the whole linked list to find the total length. Then calculate the mid point and then use this to traverse the linked list again starting from root until mid point. ...

Increasing Order Search Tree

Aug 18, 2019
One minute read

Tree traversal problems are very common in LC and this easy-level LC problem looks difficult at first but once you find out the pattern, implementing the solution in recursive way is very easy. ...

Available Captures for Rook

Aug 17, 2019
2 minutes read

I tried to simplify the solution for this easy LC problem but I guess this could’ve been the simplest I can get to. Not a beautiful code but this’ll do for now. ...

Projection Area of 3D Shapes

Aug 17, 2019
One minute read

At first, the problem looks very difficult as it involves multi-dimensional array and projections but the graph in the example really gives out the clue about how to solve this problem. ...

Maximum Depth of N-Ary Tree

Aug 15, 2019
One minute read

Easy LC problem again but this time the problem doesn’t support Kotlin yet so my solution will be in Java. ...

Sort Array By Parity II

Aug 14, 2019
3 minutes read

Here’s another easy-level LC problem. My initial solution uses two pointers: One to keep track of the index of the next even number and another for odd number. ...

Merge K-Sorted Lists

Aug 14, 2019
One minute read

This is a Hard-level Leetcode problem although the solution looks very trivial to me. ...

Squares of Sorted Array

Aug 13, 2019
One minute read

I solved this problem in like, maybe 5 seconds haha. ...

Total Hamming Distance

Aug 13, 2019
2 minutes read

My initial solution to this medium leetcode problem uses Kernighan’s way to calculate the number of 1’s in a binary: ...

Aug 13, 2019
One minute read

I really liked the solution to this problem as the code is extremely short. Thanks to Kotlin’s built-in operators. ...

Defanging an IP Address

Aug 13, 2019
One minute read

Just take a look at how easy it is to solve this Easy-level Leetcode question using Kotlin: ...

Candy Dispenser

Jun 14, 2017
4 minutes read

At Google I/O 2017, people who completed the IoT Codelabs were given an awesome reward: A Pico Maker Kit for Android Things. It’s basically another hardware development platform just like Raspberry Pi and Intel Edison. ...

Hello Android Things

Jan 12, 2017
One minute read

Moving to Silicon Valley

Sep 18, 2015
One minute read

Whoah, it’s been a while since I last blogged and all I can say is, now that I’m starting a new life in California, I think I will try to push myself to post more personal stories and technical articles. ...

GDG GeorgeTown Devfest Slides

Nov 17, 2014
One minute read

Here are the slides for the Android Wear presentation that I presented in GDG GeorgeTown’s first ever Devfest + Gdays last November 15, 2014. ...

Reading Heart Rate Data from Samsung Gear Live

Jul 8, 2014
One minute read

Here’s a quick tutorial on how to get data from the heart rate sensor in your Samsung Gear Live watch. ...

SAP Inside Track Singapore 2014

Jan 11, 2014
One minute read

Here are the slides for my talk @ SAP Inside Track Singapore 2014 entitled: Rapid Prototyping with Grails on HANA Cloud Platform. ...

Instagram Network Analysis

Dec 1, 2013
7 minutes read

Introduction Social networking has become one of the most important topics in recent times because of the several social networking sites that have now become part of our day-to-day living. There’s a huge amount of information that we can gather from analyzing these social network. ...

Network Analysis

GDG Kota Kinabalu Devfest Talk

Nov 29, 2013
One minute read

I just want to share the slides that I’ve used during my talk in GDG Kota Kinabalu Devfest last November 16, 2013. My talk is all about Arduino and Android. In the presentation, I briefly discussed the overview of Arduino and presented simple demonstrations of using Google ADK. ...

Visualizing CrazyFlie Flight Data

Oct 19, 2013
5 minutes read

In this post, we are going to explore one of the smallest quadcopters that are available in the market: CrazyFlie and how we can use node.js, d3.js, socket.io and html5 to visualize the flight data. CrazyFlie is a nano quadcopter from Bitcraze, a swedish company, whose goal is to provide an open-source hardware design and firmware for developing small quadcopters. ...

WallpaperManager and OutOfMemory

Oct 16, 2013
3 minutes read

While working on an app that sets the wallpaper in Android, I’ve encountered this weird issue with the WallpaperManager API. Initially I thought this will be a very easy and straighforward task because the WallpaperManager APIlooks simple. You just have to get an instance and call setStream() or setBitmap() depending on the type of your source. ...

Social Network Analysis and Online Courses

Oct 9, 2013
3 minutes read

So it’s my first week in the Social Network Analysis and my 4th week in Programming in Scala by Martin Odersky which are both available as online courses in coursera. I’ve tried enrolling to several online courses before but I never finish a single one because of several factors: being so lazy to work on assignments, day job, personal projects. So hopefully, I can finish at least one of them :) ...

The DigiX Development Board

Jun 25, 2013
One minute read

It’s my first time to back a Kickstarter project and it felt really good to be part of a community that helps small/budding companies launch their products. I’ve seen so many awesome Kickstarter projects before but it always felt like they are too expensive for me or I don’t have any use for them. ...

New Blog Title, new UI and Investments

Jun 19, 2013
One minute read

I’ve decided to change the blog title to something more ‘generic’ because I’m thinking of shifting the type of my posts to a mix of technical stuff and lighter topics such as personal stories and other non-technical stuff. I’ve also changed the color theme so something ‘light’ just to give it a new look. ...

Leap Motion and Android: A Match Made In Heaven

May 26, 2013
5 minutes read

Leap Motion is cool and so is Android so in this post, I’ll explain how to put them together to control a very simple fighter plane in 3D space. The example 3D application was taken from Rajawali’s example and you can take a look at its source code here. ...

Fix the missing R.java on ADT 22

May 23, 2013
0 minutes read

Connecting Android to Arduino using Bluetooth

Jul 17, 2012
6 minutes read

There are multiple ways of how you can connect an Android device to an Arduino board. You can use wifi module, a usb cable or a bluetooth module. In this post, we will try to explore the connection between the two devices using bluetooth. ...

Geocoding and Accessing Google Doc using Python Script

May 16, 2012
2 minutes read

I have a list of around 1000+ churches that contains the name of the church, simple address, the residing priest and some contains mass schedules. I thought it will be nice if we can get the latitude and longitude based on the given address. The way I do it before is to manually search the address in Google Maps and get the latitude/location by centering the marker and executing the javascript below: ...

Heart Rate Monitor using Android and Arduino

May 2, 2012
2 minutes read

Last week I decided to buy some stuff from local reseller of Arduino. I bought a Kyto Heart Sensorthat transmits heart pulses to a receiver via radio frequency. The RF receiver can then be interfaced to an arduino and then pass the results to an Android device for visualization. ...

Fixing the ADK Library to work with Arduino 1.0

Apr 6, 2012
2 minutes read

If you’ll try to create a sketch using the Android ADK library on the latest version of Arduino (1.0 as of this writing), you will get several errors just like this: Damn it I accidentally deleted the images! This is because they renamed some header files and also changed the signature of some commonly used functions. ...

How to use a Tricolor LED and a Mini Buzzer

Apr 3, 2012
3 minutes read

Controlling a Micro-Servo

Mar 29, 2012
2 minutes read

Sensing Light Variations using LDR

Mar 26, 2012
2 minutes read

Getting Started with Android and Arduino

Mar 26, 2012
5 minutes read

Writing applications on Android is cool but writing applications on Android that can talk to the physical world is totally awesome. I recently bought a Seeduino ADK Board, which is actually a clone of an Arduino board that has support for the Android Accessory Development Kit. You can find more information about Seeduino here. ...

Pixel Playground using Renderscript Compute API

Feb 22, 2012
3 minutes read

ListView Row Highlight

Feb 13, 2012
2 minutes read

Basically the idea behind this post is to show unobtrusive way of informing the user that something has changed in the data. When using ListView in Android and the backing data has changed, most of the time, I just call notifyDatasetChanged() and voila, ListView will automatically refresh the UI for me. But I noticed that this isn’t particularly good for the user as most of the time he has no idea that something has changed. ...

Sharing Apps on Android via Bluetooth

Feb 12, 2012
3 minutes read

There are times when you just want to share a particular application on your phone to a friend and as developer, I encountered this problem several times when I want to let my friend try out an application on his/her phone. ...

Phone Phreaking/Hacking

Dec 15, 2011
2 minutes read

I suddenly missed all the phone phreaking/hacking I’ve done back in 1999. It all started when someone introduced me to this group of teens calling themselves as “Liners”, most of the them are from Marikina and Pasig area. Basically these “liners” originated from cross-line party, a “bug” in the analog PSTN where multiple people can hear everyone simultaneously. ...

Oct 11, 2011
One minute read

Converting Bitmap to Grayscale

Aug 21, 2011
2 minutes read

I’m just going to share this simple snippet to convert your colored bitmap to grayscale. I’ve used this before because my application needs to communicate to a server which will just extract the image features using SURF. It doesn’t really need the color information so we decided that we can remove the color information so save up few kbps and eventually speed up the transfer. ...

Android Development using Maven

Aug 21, 2011
2 minutes read

Alphabet for Android Developers

Aug 21, 2011
One minute read

I just noticed that there are equivalent short URLs for Google’s android-related sites. I hope you’ll find this useful. ...

Custom SeekBar Preference

Aug 17, 2011
One minute read

I just would like to share the code that I’ve posted in the Google Devs mailing list when someone asked about the SeekBar Preference. This allows you to popup a seekbar that you can use to adjust some properties like volume, difficulty and other things where a slider will be useful. ...