Algorithms

Comparison of algorithms:

In this table, n is the number of records to be sorted. The columns "Average" and "Worst" give the time complexity in each case, under the assumption that the length of each key is constant, and that therefore all comparisons, swaps, and other needed operations can proceed in constant time. "Memory" denotes the amount of auxiliary storage needed beyond that used by the list itself, under the same assumption. These are all comparison sorts. The run time and the memory of algorithms could be measured using various notations like theta, sigma, Big-O, small-o, etc. The memory and the run times below are applicable for all the 5 notations.

The following table describes integer sorting algorithms and other sorting algorithms that are not comparison sorts. As such, they are not limited by a lower bound. Complexities below are in terms of n, the number of items to be sorted, k, the size of each key, and d, the digit size used by the implementation. Many of them are based on the assumption that the key size is large enough that all entries have unique key values, and hence that n << 2^k, where << means "much less than."

to know more : http://en.wikipedia.org/wiki/Sorting_algorithm

Code to determine Leap Year

if year modulo 400 is 0

then is_leap_year

else if year modulo 100 is 0

then not_leap_year

else if year modulo 4 is 0

then is_leap_year

else

not_leap_year

Longest common substring problem

http://en.wikipedia.org/wiki/Longest_common_substring_problem

Finding the longest substring in a string without repetition

http://analgorithmaday.blogspot.com/2011/05/finding-longest-substring-in-string.html

Find the longest duplicated substring in C

http://snippets.dzone.com/posts/show/6516

External Links:

http://en.wikipedia.org/wiki/Sorting_algorithm