面試題目分享

1.  http://projecteuler.net/problem=54

2.  Search a sorted array for the count of k.

Write a method that takes a sorted array A and a key k and returns the count of k.

[Hint:  Binary search commonly asks for the index of any element of a sorted array.  Find the index of the first and last occurrence of k in A.]

3.  Sort a given Perl hash by key without using Perl function sort().

4.  Implement a queue by using stacks.

[Hint:  Implement two methods enqueue() and dequeue().]

5.  Reverse the ordering of words in a string.  For example: "My name is X Y Z" to "Z Y X is name My".  Do not use tokenizers.

6.  Fibonacci spiral.

We move our finger according to Fibonacci spiral from the origin O = (0, 0). 

We will pass (1, 1), (0, 2), (-2, 0), (1, -3) in sequence.  We label the sequence in Pi, that is, P1 = (1, 1), P2 = (0, 2), P3 = (-2, 0), P4 = (1, -3) and so on.   Now write a method to return the coordinate of Pn.