How hard is Optical Character Recognition (OCR), formally? Let's assume an error tolerance comparable to a human (which is, I believe, around 98%). In other words, where would it fit in the P/NP scale of problem complexity and intractability? Or would it fit on that scale? Just what kind of problem is it? I'm not terribly familiar wit...
One thing that I've always noticed with my unit tests is that they get to be kind of verbose; seeing as they could also be not verbose enough, how do you get a sense of when your unit tests are the right size? I know of a good quote for this and it's: "Perfection is achieved, not when there is nothing left to add, but when there...
How do you know if you "Test Fixture" is right-sized. And by "Test Fixture" I mean a class with a bunch of tests in it. One thing that I've always noticed with my test fixtures is that they get to be kind of verbose; seeing as they could also be not verbose enough, how do you get a sense of when your unit tests are the right size? My ...
hello. just out of curiosity I tried to do the following, which turned out to be not so obvious to me; Suppose I have nested loops with runtime bounds, for example: t = 0 // trip count for l in 0:N for k in 0:N for j in max(l,k):N for i in k:j+1 t += 1 t is loop trip count is there a general algorithm/...
I had someone advise me to avoid repeatedly calling String.Length, because it was recalculated each time I called it. I had assumed that String.Length ran in O(1) time. Is String.Length more complex than that? ...
is it possible to write a program which prints its own source code utilizing a "sequence-generating-function"? what i call a sequence-generating-function is simply a function which returns a value out of a specific interval (i.e. printable ascii-charecters (32-126)). the point now is, that this generated sequence should be the programs ...
Swanepoel's comment here lead me to this paper. Then, searching for an implementation in C, I came across this, which referenced another paper on an algorithm described here. Both papers describe integer sorting algorithms that run in O(nloglog(n)) time. What is the difference between the two? Have there been any more recent findings ...
Possible Duplicate: Interview Q: given an array of numbers, return array of products of all other numbers (no division) I came across an interview task/question that really got me thinking ... so here it goes: You have an array A[N] of N numbers. You have to compose an array Output[N] such that Output[i] will be equal to mul...
I would like to know the complexity (as in O(...) ) of the following sorting algorithm: There are B barrels that contain a total of N elements, spread unevenly across the barrels. The elements in each barrel are already sorted. The sort combines all the elements from each barrel in a single sorted list: using an array of size B to ...
Hello, I'm still learning about complexity measurement using the Big O Notation, was wondering if I'm correct to say that following method's complexity is O(n*log4n), where the "4" is a subscript. public static void f(int n) { for (int i=n; i>0; i--) { int j = n; while (j>0) j = j/4; } } ...
Let's suppose I want to "protect" this code about being used without attribution, patenting it, or through any open source licence... #include<stdio.h> int main (void) { int version=2; printf("\r\n.Hello world, ver:(%d).", version); return 0; } It's a little obvious or just a language definition example.. When a source ...
If LinkedHashMap's time complexity is same as HashMap's complexity why do we need HashMap? What are all the extra overhead LinkedHashMap has when compared to HashMap in Java? ...
Binary search has a average case performance as O(log n) and Quick Sort with O(n log n) is O(n log n) is same as O(n) + O(log n) ...
Hi, I'm using .NET 4's System.Numerics.BigInteger structure. I need to calculate the square (x2) of very large numbers - millions of decimal digits. If x is a BigInteger, What is the time complexity of: x*x; or BigInteger.Pow(x,2); ? How can multiply such big numbers in the fastest way using .NET 4 BigInteger? Is there an imple...
Hi, I'm having problems to recall the name of doing something with quadratic complexity when it can be solved linearly. For example, using a get-by-index function to iterate over a linked list instead of just using a next-element is the typical case of this antipattern. I think it was the "something painter", as a metaphor of a guy tha...
Hi again, Few more problems I ran into calculating the Big-oh complexity. There are 2 problems which I cannot solve due to log base operations. Here are the two problems: n = # of data items being manipulated 1) n^3 + n^2 log (base 2) n + n^3 log (base 2) n 2) 2n^3 + 1000n^2 + log (base 4) n + 300000n I am confused when the logs ha...
How to remove blank spaces in a string with a complexity of O(n). My approach is using two indexes. One will traverse till length on string. Other will be incremented only when a non-blank character is encountered. But i am not sure of this approach. TIA, Praveen ...
In the introduction to Bruce Eckel's Thinking In Java, he says, in 1998: Programming is about managing complexity: the complexity of the problem you want to solve, laid upon the complexity of the machine in which it is solved. Because of this complexity, most of our programming projects fail. And yet, of all the program...
Is there a way to generate all of the subset sums s1, s2, ..., sk that fall in a range [A,B] faster than O((k+N)*2N/2), where k is the number of sums there are in [A,B]? Note that k is only known after we have enumerated all subset sums within [A,B]. I'm currently using a modified Horowitz-Sahni algorithm. For example, I first call it t...
As the title suggests, what is the runtime complexity (eg, big-O) of the Sprite.contains method? ...