Category Archives: Programming

In this category, it includes data structure, algorithms and some interview questions.

Chapter 1. Arrays and Strings

Posted on by
Reply

 

  1. Implement an algorithm to determine if a string has all unique characters. What if you cannot use additional data structures? [C++]
  2. Implement a function void reverse(char* str) in C or C++ which reverses a null-terminated string. [C++]
  3. Given two strings, write a method to decide if one is a permutation of the other. [C++]
  4. Write a method to replace all spaces in a string with ‘%20’. You may assume that the string has sufficient space at the end of the string to hold the additional characters, and that you are given the “true” length of the string. (Note: if implementing in Java, please use a character array so that you can perform this operation in place.)[C++]
    EXAMPLE
    Input: “Mr John Smith ”
    Output: “Mr%20John%20Smith” Continue reading →

8051 Development Tool

Posted on by
Reply

Current Features:

  1. Read a Intel Hex file (compiled by Keil uVision4)
  2. Generated a memory table which is used to write to AT89S52 microcontroler (8-Bit Microcontroller, 8KB ISP Flash)
  3. Converted the table into another format: 5F=0; DF=1 (the actual data that will be written to the device)
  4. Listed all usb devices

Unfinished parts:

  1. Read/write data from/to AT89S52 microcontroler

Continue reading →

A Link-level Simulator over Wireless Channels

Posted on by
Reply

In this project, we create a link-level Monte-Carlo simulator. Then, we analyze the performance of convolutional codes over different wireless channels: additive white Gaussian noise(AWGN) and Rayleigh fading.

We use following blocks to implement our simulator: source generator, encoder/decoder, inter-leaver/deinterleaver, modulator/demodulator, and wireless channel.

Development tool: Matlab 2012a with Communication toolbox

Continue reading →

Price Comparison Service Based on Hadoop

Posted on by
Reply

Web-shopping is popular and widely used nowadays; however, comparing price difference among various platforms is tedious and inefficient for customers. A customer might be interested in a particular brand but have no concrete idea what model he/she is going to buy. In this work, we will provide a suggestion for users which platform has cheapest laptops of a certain brand to help them make choices. Because of the large amount of laptop models in the market, the comparisons would become a time-consuming job. Therefore, we are interesting in the performance improvement which Hadoop can bring to us if we partition the workload into parallelism.

Comparing price difference between two web-shopping platforms, we must get the price of a certain model from one platform and then search the same model on the other one. This operation is similar to do equijoin on the same model on two websites.
However, with the help of robust search function in these websites, we can utilize it as index to facilitate our equijoin and therefore minimize the time and resource for our service.
The flow of our program is stated as follows:

 

Continue reading →

Modeling of a Canny Edge Detector System-on-Chip (SoC)

Posted on by
Reply

We aim to develop a real-time edge detection system on a chip for a digital camera. We design a model of canny edge detector application and represent it in the SpecC system-level description language (SLDL) so that the design model can be used for implementation as a System-on-Chip (SoC) suitable for use in a digital camera. Then, we use System-on-Chip Design Environment (SCE), a refinement-based framework, to analyze our system. Besides, we assign a processor, hardware units and buses to meet realtime requirements.

 

Continue reading →