Tuesday, July 22, 2008

Garmin GPS

I have been using GPS navigation devices for sometime. I was told Garmin was the best brand for GPS. It's hard to judge how good a brand could be unless one uses some other variety. So, last week, I rented a Hertz car in which they had already installed a GPS which was custom made. I would say, the GPS only helped me find a route between a source and a destination. The interface was not friendly at all - it was not a touch screen and the keypad prompted every key I pressed a key. Pressing the letters and numbers was inconvenient. Morevoer, there was no option to search for businesses close to a place. It happened that I pulled over the car and searched for the Starbucks cafe. However, it returned all addresses in different states and cities. I realized that I was standing next to a Starbucks cafe and the GPS failed to locate it. What a performance !

It is obvious that the Garmin GPS is indeed among the best. First of all, the vendors underestimate the value of simplicity and user-friendly (Google-like interface). The interface needs to be touch screen. It's a pain to punch in keys. Today I was traveling from LA to Riverside and the traffic on the freeway was extremely bad. However, the Garmin GPS kept finding alternative routes for me. The GPS takes into consideration an existing congestion in the freeway. For example, at one point of time, it told me to take an exit and re-enter the same freeway from the right side (it was awesome that I could cut through the traffic for 1/2 mile several times). It does many other optimization to save time. Another feature that I like in Garmin GPS is the option to localize near by attractions, restaurants etc.

Interesting thing is that all the GPS devices have the same broadcasted information from a satellite, still there is so much difference in performance.

Thursday, July 17, 2008

More Interview Questions:
As I went through more interviews, I was asked some interesting questions. If you happen to know the solutions or want to know the solutions, you write to me.

[1] Given an array of n integers both positive and negative integers. Find the sub-sequence of the array which has the largest sum. Find the algorithm with a better complexity than brute force one.

[2] Given a character array, print all the palindromes. Find an efficient algorithm.

[3] Write a C program to show if stack is growing into higher memory.

[4] How to make a server accept client connections in a non-blocking mode efficiently ?

[5] Find the Kth largest element in a binary search tree.

[6] Many more to come ...