Asadullah Ansari

Build-Up Your Problem Solving Skill : Specially Using By C/C++/Data Structure Puzzles/New Technique Algorithm Design/ Understanding New Technology

Catch all the startup action @ Siliconindia Startup City

Posted by asadullahansari on May 27, 2011

Hi guys/dudes/gentleman…

As you know the average inflation rate in India is 7.99 percent so i didn’t believe in saving money by fixed deposit or mutual funds or any investment plan if i will believe that’s  directly involved into share market But I believe the most important to investment business investment…Now-a days  Businesses are fizzing out and the investment is at an all time low and world is moving too fast as you can’t imagine.. But Hey Guys! this does not deter the young minds in the country.. Almost 75% of them have found the current market scenario to be the opportunity to innovate and create tornadoes that would rip the market and bring in new business opportunities.

You can come with new ideas/new innovation/new business plan and create your own world… 🙂

Here siliconindia.com provides a platform to discuss your ideas and get new business plan for your own startup and all…

Siliconindia brings to you some of these risk loving entrepreneurs and their mind boggling products ..

Here’s what one will get at siliconindia  StartupCity

  • 100 Startups to showcase in the presentation rooms& respective booths
  • More than 50VC firms to attend & judge the presenting Startups
  • Awards to Best Startup in 10 Categories
  • Significant presence of partner companies and potential customers
  • Over 500 Startup companies to participate
  • Over 5000 delegates to attend the product demos at booths
  • Special VC-Entrepreneur-Partner Company Breakfast & Lunch
  • Over 400 CEOs & MDs at the CEO Conclave
Tomorrow siliconindia is providing to you to get ideas from entrepreneur so guys if you are willing to go there and explore yourself n map to world class business . Detail is as

Startup City Bangalore 2011 – SiliconIndia

on May 28 2011 9:00 am to May 28 2011 6:00 pm
At
Bengaluru, Karnataka
Nimhans Convnt Center, near Dairy Circle
link is

Posted in Uncategorized | Leave a Comment »

Google Interview Latest

Posted by asadullahansari on September 4, 2008

Google telephonic Interview

1. Asked about my project. Prepare well to answer any type of questions that may arise in your project.They will just ask to explain about any one of the projects listed in your resume.
2. In a plane, n points are given i.e. the input is (x1,y1), (x2,y2)… (xn,yn). Now given these n points.Find the maximum number of collinear points.
Solution:
The duality algorithm would work. Find the point of intersection with maximum no of lines incident on it in the dual plane. It works in O(n^2).
3. Write the code for finding the min of n number.

for(i=0;i<n;i++)
{
if( a[i]<min )
{
min = a[i] —- eq(i)
}
}

Given that n numbers are from random sampling how many times (probability) does the line (i) be executed

Solution:

min=a[0];
for(i=1;i<n;i++)
{
if( a[i]<min )
{

min = a[i]; ——-eq(i)
}

}

Once the variable min is initialized,the probability of a[i] =k)
{
count+=n/k;
k*=5;
}
return count;
}

this count is the number of o’s in n!.

Google Interview Round 3 :

1. Write C++ class for the game Connect Four. [Connect Four (also known as Plot Four, Four In A Row, and Four In A Line) is a two-player board game in which the players take turns in dropping discs into a seven column grid with the objective of getting four of one’s own discs in a line.]

2. Given a stack and an input string of 1234.At any point you can do anyone of the follow

i. take the next input symbol and Enque.
ii. you can pop as many as you can. When ever you
pop an element it will be printed
(you cannot pop from an empty stack)

How many such permutations are possible on an input of size N?

Solution:
It is Nth catalan number.For a detailed solution look at question5 of Stacks and Queues

3. Give an example of one permutation that this data structure cannot generate.

For Example:

1234 is input.

First push all 1,2,3,4 on to stack and pop all.
output will be 4321.

It means that this data structure can generate 4321.

Solution:
3124
for a detailed solution please look at question7 of the post
Stacks and Queues

4. Question 2 was pretty easy right? Now do again the same question but the data structure this time around is a Deque.

Input: 12345
Data Structure: Deque ( Doubly Que )

Note: Deque is a data structure into which you can do enque
and deque from both sides.Some thing like this
__________________________________
enque —> <—-enque dequeue dequeue
__________________________________

Solution:
It is N!. Guess why?(no constraints).Convince yourself by proving that every permutation can be generated by a set of valid operations.This prove can be using the principle of strong mathematical induction.So for this specific input the answer is 120.

5. Classic Egg Puzzle Problem You are given 2 eggs.You have access to a 100-store building. Eggs can be very hard or very fragile means it may break if dropped from the first floor or may not even break if dropped from 100 th floor.Both eggs are identical.You need to figure out the highest floor of a 100-store building an egg can be dropped without breaking. Now the question is how many drops you need to make. You are allowed to break 2 eggs in the process.

Solution:
Let “d” be the number of drops required to find out the max floor.we need to get the value of d.

let’s say if we drop from height d then if it breaks then we have d-1 floors to check for the second egg . so max of “d” drops, so first we will drop it from height “d” if it doesn’t break at a height “d” then we are left with “d-1” drops,so lets drop it from d + ‘d-2’ + 1 height suppose if it break there then you are left with ‘d-2’ drops.
and so on until that sum is less than 100, it’s like a linear search,

in equations,

(1+(d-1))+ (1+(d-2)) + …. >= 100

here we need to find out d

from the above equation

d(d + 1)/2 >= 100

from above d is 14

Google Interview Round 4 :

1. Given n non overlapping intervals and an element. Find the interval into which this element falls.

Solution:
we can extend binary search to intervals.(Assuming the intervals are sorted)
consider interval [a,b].
if (a-x)(b-x) a
element can be present only in the intervals to its right.
so select the middle interval among them to it’s right
and repeat the procedure.
else
element can be present only in the intervals to its left.
so select the middle interval among them to it’s left
and repeat the procedure.

The complexity of this problem is log(N) where N is the number of sorted non-overlapping intervals.

2. Worst case is take all intervals one at a time and see whether the element lies in the interval or not.It will take O(n). So please give a solution that will do better than O(n).

3. Now given that the n intervals are overlapping then how do you solve? The interviewer was concentrating more on the complexities (running, memory ..)

Solution:
If the above intervals are overlapping ,then they can be merged in O(N) and then the exact intervals can be resolved later.Otherwise ,we can identify one correct interval and then linear search on its left and right neighbourhood to find the other solutions.

4. Write code for Random Sort?

Algorithm is explained:

Given an input array of size n. Random sort is sampling
a new array from the given array and check whether the
sampled array is sorted or not. If sorted return else
sample again. The stress was on the
code.

Google Interview Round 5: This is Manager Round

1. Tell me an achievement that you have done in your non academics

2. Tell me about one of your project

3. Take a feature of C++ and tell me how you have implemented it in one of your project

4. By taking one of your project as example tell me how you have taken care of software engineering where you would have handled more data

5. There is a routine already written to find the subtraction of two sets ( set A – set B) . Write test cases for testing it.Tell me how do you test the test cases you have written?

6. There is a printed book. The page numbers are not printed. Now the printing of page numbers is being done separately. If the total number of digits printed is 1095 then how many pages does the book have?

Solution: Well people,this is too simple a question ..so do give it a try..(no malice,too simple).Any queries then do shoot a comment.

Reference: http://placementsindia.blogspot.com/2007/08/google-freshers-latest-interview.html

Posted in 1 | 2 Comments »

Freeze your mind!!!!

Posted by asadullahansari on August 22, 2008

A bank has a collection of n bank cards that they�€™ve confiscated, suspecting them of being used in a fraud. Each bank card corresponds to a unique account in the bank. Each account can have many cards corresponding to it, and we�€™ll say that two bank cards are equivalent if they correspond to the same account. The only way to say 2 cards are equivalent is by using a high-tech �€œequivalence-tester�€� that takes in 2 cards, and after performing some computations, determines whether they are equivalent.

Their question is the following: among the collection of n cards, is there a set of more than n/2 of them that are all equivalent to one another? Assume that the only feasible operations you can do with the cards are to pick two of them and plug them in to the equivalence tester.
Solve it in O(n) complexity.

Posted in Queries & Answers | Tagged: , | Leave a Comment »

write a program for bit count in a 32-bit integer number?

Posted by asadullahansari on August 21, 2008

Program should be efficient. Dont count every bit by loop…Cheers!!!!

Posted in C/C++ Queries & Ans | 1 Comment »

Appreciation plays Important role to develope problem solving skill !!! Believe it!!!

Posted by asadullahansari on August 21, 2008

You read this Example!!!

Appreciation Advantage

Gather Information from facts More and More or as much as possible

Lot of people does not understand appreciation and someone understand but not able to implement it. Appreciation is not a tough but it’s very simple but One thing it’s Very powerful technique to gather More and More Information from people, from employee, etc. By using this technique in both ways improvement example : In an organization, If Manager use this technique then it’s benefit for organization , as for skill developement of employee, Manager aspects satishfaction etc. So cheers to use this skill.

I will take a example of Military Sytem who are making plan.
Example: Military Planners

Fact: It rained heavily last night

So What? //

– The ground will be wet

So What?

– It will turn into mud quickly

So What?

– If many troops and vehicles pass over the same ground, movement will be progressively slower and more difficult as the ground gets muddier and more difficult.

So What?

– Where possible, stick to paved roads. Otherwise expect movement to be much slower than normal.

While it would be possible to reach this conclusion without the use of a formal technique, Appreciation provides a framework within which you can extract information quickly, effectively and reliably.

Key points:

>> Asking ‘so what?’ repeatedly helps you to extract all important information implied by a fact.

>> Just listen all possible solutions it may be at all not useful but still appreciate his things and keep asking to gather more and
more information

>> Appreciation can be used to recuitement of good employees.

>> Appreciation can make employee- manager relationship good and by this method you can get more excellent solutions than
not using appreciation.

>>

Posted in Tips to Improve Skills | Leave a Comment »

Give the optimized algorithm for this?

Posted by asadullahansari on August 20, 2008

Suppose a number is given. You have to write an algorithm to find sum of two elements of a given array which should equal to a given number.

Example:
arr[]={ 2,5 ,7 ,9 ,4 ,6 ,8 }
a number give nSum= 17

then You have to find elements 9 and 8.

Posted in Algo design: Queries | Leave a Comment »

solve this puzzle?

Posted by asadullahansari on August 20, 2008

Two boys walking in the woods decide to take a shortcut thru a railroad tunel. When they had walked 2/3 of the way, their worst fears were realized. A train was coming in the opposite direction, nearing the tunnel entrance. They boys panicked and each ran for a different end of the tunnel. Both boys ran at the same speed, 10 miles per hour Each boy escaped from the tunnel just at the instant the train would have squashed him. Assuming the train’s speed was constant, and both boys were capable of instantaneous reaction and acceleration, how fast was the train going?

Posted in Queries & Answers | Tagged: | 4 Comments »