# Tagged Questions

122 views

### How to construct a cubie representation of a rubik's cube, given an array

Just to get this out of the way, I have seen this, and it is not what I'm looking for. So, let's say you are programming a Rubik's Cube. (I know, very unoriginal, but bored programmers have to do ...
43 views

### Search substring using suffix array (and LCP)

I'm searching for a best way to improve suffix array run time using LCP. My text (about 2 500 000 chars) seems like: 0ricco0eric0america0polo0.... My thoughs: SA=suffixArray char=firstChar(input) s ...
155 views

### Sorting an array when values are decreased by each swap [closed]

Recently in an interview I come across a question: We have an unsorted array, we need to sort it with minimum number of swap. We have in sort a 'tax' of 1 is deducted from the number we are ...
298 views

### Quick algorithm to find matches between two arrays

I'm faced with the following problem: I have an array which is produced by the parsing of a yaml file which contains patterns in the following structure. "Programming books" Title: a ...
641 views

### Find all lines segments intersections

I have a collection of lines segments, represented by an array. Ex: [3,7,13,6,9] is 4 line segments: [(3,7)(7,13)] , [(7,13)(13,6)] , [(13,6)(6,9)] , ([6,9)(9,3)] I want to find all the lines ...
1k views

### Reverse subarray of an array with O(1)

I have an idea how to implement sub array reverse with O(1), not including precalculation such as reading the input. I will have many reverse operations, and I can't use the trivial solution of O(N). ...
168 views

### What would be the optimal way to solve a problem like this?

I have a problem where I have to change all the Xs in a 2D array into 0s, and I have to calculate the minimum steps (where a single step consists of changing an entire row or column) required to do ...
159 views

### What is the name of this array transformation?

Start with an array of arrays; in this case, they are different lengths in order to demonstrate the technique, but they do not have to be. [[1,2,3,4], [5,6,7], [8,9,10], [11,12,13,14,15]] At the ...
1k views

### Retrieving maximum value from a range in unsorted array

I have an unsorted array. I have queries in which I give a range and then the maximum value from that range has to returned. For example: array[]={23,17,9,45,78,2,4,6,90,1}; query(both inclusive): 2 ...
1k views

### How do you find the first common element in two arrays

The way I did it was to loop through each at the same time and add the current value to a separate set for each of the lists. Also, check if the current element is already in the other list's set. I ...
470 views

### A simple algorithm for finding duplicate floats [closed]

We have N numbers(real numbers(float)).They can be positive or negative or anything we do not know except the fact that there is exactly one number which has a duplicate and the rest all are distinct. ...