RARE QUESTIONS

Reverse a linked list. Posted: The answer is that you need to store all possible configurations of the board and the move that is associated with that. Then it boils down to just accessing the right element and getting the corresponding move for it. Do some analysis and do some more optimization in storage since otherwise it becomes infeasible to [...]

Give a very good method to count the number of ones in a “n” (e.g. 32) bit number. Posted: Given below are simple solutions, find a solution that does it in log (n) steps. Iterative function iterativecount (unsigned int n) begin int count=0; while (n) begin count += n & 0×1 ; n >>= 1; end return count; end Sparse Count function sparsecount (unsigned int n) begin int count=0; while (n) begin count++; n [...]

Given only putchar (no sprintf, itoa, etc.) write a routine putlong that prints out an unsigned long in decimal. Posted: I gave the obvious solution of taking % 10 and / 10, which gives us the decimal value in reverse order. This requires an array since we need to print it out in the correct order. The interviewer was not too pleased and asked me to give a solution which did not need the array

Consider a number 235, where last digit is the sum of first two digits i.e. 2 + 3 = 5. How many such 3-digit numbers are there? Posted: There are 45 different 3-digit numbers. The last digit can not be 0. If the last digit is 1, the only possible number is 101. (Note that 011 is not a 3-digit number) If the last digit is 2, the possible numbers are 202 and 112. If the last digit is 3, the possible numbers are 303, [...]

How long would it take you to count 1 billion orally if you could count 200 every minute and were given a day off every four years? Posted: Assume that you start counting on 1 January 2001. 9 Years, 187 Days, 5 Hours, 20 minutes As you can count 200 per minute, to count 1 billion you require = 1,000,000,000/200 minutes = 5,000,000 minutes gy majors, & 62% are business majors. If there are 200 students, how many of them are majoring in both [...]

At University of Probability, there are 375 freshmen, 293 sophomores, 187 juniors, & 126 seniors. One student will randomly be chosen to receive an award. What percent chance is there that it will be a junior? Round to the nearest whole percent Posted: Divide the number of juniors (187) by the total number of student (981), & then multiply the number by 100 to convertto a percentage. Hence the answer is (187/981)*100 = 19%

Jack and Jill are playing cards for a stake of $1 a game. At the end of the evening, Jack has won 3 games and Jill has won $3. How many games did they play? Posted: They played total of 9 games. Jack won 3 games and Jill won6 games. If Jack has won three games and Jill has won $3, she lost adollar for each loss, therefore she has won 6 and lost 3 to make $3 and he won the other 3 that she lost

A man got 30 aples in 1 Rs.Now he want 20% of profit on it. How many apples He should Sell in 1 Rs.?? Posted: 24.(logical xpln) assume 100 rs & 30 apples.i.e 3.33/ apple. for 20 % profit i.e 20 rs, each apple 2 b sold at 4 rs. but he has to sell it in rs 100 therefore no of apples shud b reduced. to earn 20 rs =3.33*(6) approx.therefore 6 less apples thus 24 apples

A circle of a playground is to be fenced at circumference.The cost of the fencing is Rs.150 per sqm. what is the total cost , if the diameter is 70? Posted: Rate should be Rs 150 per meter (not sqm). (Rs 150 / m) * circumference = (Rs 150 / m) * pi * diameter = (Rs 150 / m) * (22/7) * 70 m = Rs 150 * 22 * 10 = Rs 33000

Posted: Could you please explain me how you got 6 as your answer. I could do it in a minimum of 11 races. There has to be atleast 5 races to select 15 horses. The 15 horses then compete among themselves and best 9 horses are chosen. The 9 horses then run in groups of 5 [...]

Find out the smallest four digit number which is divisible from 1 to 10? Posted: 1050. I multiplied all the prime numbers from 1 - 10 and then found its(210) smallest 4 digit multiple which is 1050

I can take a bca student instead of you then why should i hire you Posted: You can get a uneducated person for 1/4 to 1/10 of salary why don’t you hire him. Answer is quality, understanding, future value addition etc.

Two trains at speed 60 km/hr comes in the opposite direction. At a particular time the distance between the two trains is 18km. A shuttle flies between the trains at the speed of 80 km/hr. At the time the two trains crashes what is the distance traveled by shuttle? Posted: Here the realative speed is 60+60=120kms/hr…. The distance between them was 18kms when the shuttle begins to fly in between them….. To cover 18 kms with a relative velocity of 120 kms/hr the time would be 18/120,ie,=3/20 so shuttle can fly ((3/20)*80) kms before the two trains crashes,so the answer is 12 kms…

You’ve got someone working for you for seven days and a gold bar to pay them. The gold bar is segmented into seven connected pieces. You must give them a piece of gold at the end of every day. If you are only allowed to make two breaks in the gold bar, how do you pay your worker? Posted: Break the gold bar at 3 position then u will get 2(1,2),1(3),4(4,5,6,7) combination gold bar and break at middle in 4 segment (4,5,6,7)in middle so that there will be 2 segment combination(4,5)and (6,7) at 1st day the owner gives 1 the 2nd day he gives 2 and takes 1 and 3rd day he gives 1,4th [...]

You have 8 balls. One of them is defective and weighs less than others. You have a balance to measure balls against each other. In 2 weighings how do you find the defective one? Posted: Take 3 and 3 balls in each of balance and keep other 2 aside.If there is any defective ball in 3 balls either there will beunbalance.if so take those 3 balls aside which has no defective ball.

Given a rectangular (cuboidal for the puritans) cake with a rectangular piece removed (any size or orientation), how would you cut the remainder of the cake into two equal halves with one straight cut of a knife? Posted: Join the centers of the original and the removed rectangle. It works for cuboids too! BTW, I have been getting many questions asking why a horizontal slice across the middle will not do. Please note the “any size or orientation” in the question! Don’t get boxed in by the way you cut your birthday cake [...]

Can you tell who is the Doctor and the Engineer? Posted: Mr. Bajaj’s wife and mother are not blood relatives. So from 3, if the Engineer is a female, the Doctor is a male. But from 1, if the Doctor is a male, then the Engineer is a male. Thus, there is a contradiction, if the Engineer is a female. Hence, either Mr. Bajaj or his [...]

The question is how much distance did the last person cover in that time. Assuming that he ran the whole distance with uniform speed. Posted: The last person covered 120.71 meters. It is given that the platoon and the last person moved with uniform speed. Also, they both moved for the identical amount of time. Hence, the ratio of the distance they covered - while person moving forward and backword - are equal. Let’s assume that when the last person reached the [...]

Three friends divided some bullets equally. After all of them shot 4 bullets the total number of bullets remaining is equal to the bullets each had after division. Find the original number divided. Posted: Assume that initial there were 3*X bullets. So they got X bullets each after division. All of them shot 4 bullets. So now they have (X - 4) bullets each. But it is given that,after they shot 4 bullets each, total number of bullets remaining is equal to the bullets each had after division i.e. X Therefore, the equation [...]

You have to draw 3 concentric circles with a line passing thru their centerwithout lifting hand. Posted: Start the line complete one circle move inside circles along the line and then draw second circle. Like wise rest.