|
|
4GuysFromRolla.com |
[Search]
|
|
Microsoft Interview Question Answers
Read the Interview Questions...
Here are the answers to the Microsoft Interview Questions.
You are given a scale which you are to use to measure eight balls. Seven of these balls
have the same weight: the eigth ball is heavier than the rest. The scale does not indicate
the weight of a particular object; it is a scale which tells you which of the two sides
being weighed is heavier (like the scale that lady of justice statue holds up). So, for
example you could place one ball on each end of the scale. If ball one was heavier than
ball two, it would tip in ball one's direction; if ball two were heavier, it would tip io
ball three's direction; if the balls were of equal weight, the scale would not tip at all.
What is the minimum number of weighs you could perform to find the heaviest of the
eight balls?
Answer: You can do this in 2 weighs. Put three balls on each side of the scale. That's a total
of six balls you're weighing. If the three balls on each side weigh equally, you know that one of the
two remaining balls is the heaviest. Weigh those two balls to determine which one is heaviest. If, however,
one of the three ball combinations weighs most, remove all balls from the scale, then weigh just two of the
three "heavier" balls. If those two balls are equal weight, the third, unweighed ball is the heaviest; otherwise
the scale will indicate which of the two balls on the scale is the heavy one.
Imagine that you have 26 constants, labelled A through Z. Each constant is assigned a
value in the following way: A = 1; the rest of the values equal their position in the
alphabet (B corresponds to the second position so it equals 2, C = 3, etc.) raised to the
power of the preceeding constant value. So, B = 2 ^ (A's value), or B = 2^1 = 2. C = 3^2
= 9. D = 4^9, etc., etc. Find the exact numerical value to the following equation:
(X - A) * (X - B) * (X - C) * ... * (X - Y) * (X - Z)
Answer: Well, since we have a series of products here, X - X will soon be reached, which will equate to zero.
Throwing zero into a product results in an answer of zero. So, the answer is zero. Easy, eh? :)
Write C code to implement atoi
Answer: Does anyone really want to know this one? If so,
just let me know, and I will post the answer...
And fimally, the hum-dinger: There are four people who need to cross a bridge at night.
The bridge is only wide enough for two people to cross at once. There is only one
flashlight for the entire group. When two people cross, they must cross at the slower
member's speed. All four people must cross the bridge in 17 minutes, since the bridge will
collapse in exactly that amount of time. Here are the times
each member takes to cross the bridge:
- Person A: 1 minute
- Person B: 2 minutes
- Person C: 5 minutes
- Person D: 10 minutes
How can all four people get across the bridge within 17 minutes?
Note: there is no trick-answer to this problem. You can't do tricky stuff like
throwing the flashlight back from one end of the bridge to the other. This problem can
be solved!
Answer:
A and B cross together. Total Time: 2 Minutes
A comes back. Total Time: 3 Minutes
C and D cross together. Total Time: 13 Minutes
B comes back. Total Time: 15 Minutes
A and B cross together. Total Time: 17 Minutes
See, it is possible! :)
|
|