Add time and space complexity information to various algorithms (#744)

* Add time and space complexity information to various algorithms

* Added the implementation of Kosaraju algorithm

* Added some style issues in articulationpoints.go

* Formatted code with gofmt -s to meet style requirements

---------

Co-authored-by: Rak Laptudirm <[email protected]>

Author: mapcrafter2048

cache/lru.go

@@ -1,3 +1,10 @@
+// lru.go
+// description : Least Recently Used (LRU) cache
+// details : A Least Recently Used (LRU) cache is a type of cache algorithm used to manage memory within a computer. The LRU algorithm is designed to remove the least recently used items first when the cache reaches its limit.
+// time complexity : O(1)
+// space complexity : O(n)
+// ref : https://en.wikipedia.org/wiki/Cache_replacement_policies#Least_recently_used_(LRU)
+
 package cache
 
 import (

checksum/crc8.go

@@ -3,6 +3,8 @@
 // details:
 // A cyclic redundancy check (CRC) is an error-detecting code commonly used in digital networks
 // and storage devices to detect accidental changes to raw data.
+// time complexity: O(n)
+// space complexity: O(1)
 // See more [CRC](https://en.wikipedia.org/wiki/Cyclic_redundancy_check)
 // author(s) [red_byte](https://github.com/i-redbyte)
 // see crc8_test.go

checksum/luhn.go

@@ -1,6 +1,8 @@
 // lunh.go
 // description: Luhn algorithm
 // details: is a simple checksum formula used to validate a variety of identification numbers, such as credit card numbers, IMEI numbers, etc [Lunh](https://en.wikipedia.org/wiki/Luhn_algorithm)
+// time complexity: O(n)
+// space complexity: O(1)
 // author(s) [red_byte](https://github.com/i-redbyte)
 // see lunh_test.go
 

cipher/caesar/caesar.go

@@ -1,4 +1,8 @@
 // Package caesar is the shift cipher
+// description: Caesar cipher
+// details : Caesar cipher is a type of substitution cipher in which each letter in the plaintext is shifted a certain number of places down the alphabet.
+// time complexity: O(n)
+// space complexity: O(n)
 // ref: https://en.wikipedia.org/wiki/Caesar_cipher
 package caesar
 

cipher/diffiehellman/diffiehellmankeyexchange.go

@@ -1,4 +1,8 @@
 // Package diffiehellman implements Diffie-Hellman Key Exchange Algorithm
+// description: Diffie-Hellman key exchange
+// details : Diffie-Hellman key exchange is a method of securely exchanging cryptographic keys over a public channel by combining private keys of two parties to generate a shared secret key.
+// time complexity: O(log(n))
+// space complexity: O(1)
 // for more information watch : https://www.youtube.com/watch?v=NmM9HA2MQGI
 package diffiehellman
 

cipher/polybius/polybius.go

@@ -1,4 +1,8 @@
 // Package polybius is encrypting method with polybius square
+// description: Polybius square
+// details : The Polybius algorithm is a simple algorithm that is used to encode a message by converting each letter to a pair of numbers.
+// time complexity: O(n)
+// space complexity: O(n)
 // ref: https://en.wikipedia.org/wiki/Polybius_square#Hybrid_Polybius_Playfair_Cipher
 package polybius
 

cipher/railfence/railfence.go

@@ -1,3 +1,9 @@
+// railfence.go
+// description: Rail Fence Cipher
+// details: The rail fence cipher is a an encryption algorithm that uses a rail fence pattern to encode a message. it is a type of transposition cipher that rearranges the characters of the plaintext to form the ciphertext.
+// time complexity: O(n)
+// space complexity: O(n)
+// ref: https://en.wikipedia.org/wiki/Rail_fence_cipher
 package railfence
 
 import (

cipher/rot13/rot13.go

@@ -1,4 +1,8 @@
 // Package rot13 is a simple letter substitution cipher that replaces a letter with the 13th letter after it in the alphabet.
+// description: ROT13
+// details: ROT13 is a simple letter substitution cipher that replaces a letter with the 13th letter after it in the alphabet. it is a special case of the Caesar cipher
+// time complexity: O(n)
+// space complexity: O(n)
 // ref: https://en.wikipedia.org/wiki/ROT13
 package rot13
 

cipher/rsa/rsa.go

@@ -6,6 +6,8 @@
 // thus both the Encrypt and Decrypt are not a production
 // ready implementation. The OpenSSL implementation of RSA
 // also adds a padding which is not present in this algorithm.
+// time complexity: O(n)
+// space complexity: O(n)
 // author(s) [Taj](https://github.com/tjgurwara99)
 // see rsa_test.go
 

cipher/rsa/rsa2.go

@@ -2,6 +2,8 @@
 rsa2.go
 description: RSA encryption and decryption including key generation
 details: [RSA wiki](https://en.wikipedia.org/wiki/RSA_(cryptosystem))
+time complexity: O(n)
+space complexity: O(1)
 author(s): [ddaniel27](https://github.com/ddaniel27)
 */
 package rsa