algorithms_and_data_structures

Data Structure and Algorithms Problems

Current Status	Stats
Total C++ Problems	188
Total Python Problems	15
Current Daily Streak	11
Last Streak	06/20/2019 - 06/21/2019
Current Streak	06/23/2019 - 07/03/2019

Note: Some of the code here is old and was written when I was learning C++. It might be possible that code is not safe or making wrong assumptions. Please use with caution. Pull requests are always welcome.

LinkedList Problems

Problem	Solution
Find the nth node of linked list from last.	nthToLastNode.cpp, nth_to_last_node.py
Add numbers where each digit of the number is represented by node of a linkedlist. Give output as a linked list.	add_two_numbers_lists.cpp, add_two_numbers_list.py
Swap nodes of a linkedlist without swapping data.	swapNodesWithoutSwappingData.cpp, swap_nodes_without_swapping_data.py
Reverse a linked list, iteratively and recursively	reverseLinkedListIterAndRecurse.cpp, reverse_linkedlist.py
Given a linked list, reverse alternate nodes and append at the end.	reverseAlternateNodes.cpp
Only given a node pointer, delete the node from the linked list.	deleteNode.cpp
Delete the entire linkedlist.	deleteLinkedlist.cpp
Print middle node of linkedlist without iterating twice.	printMiddleNode.cpp
Determine if a linked list is a pallindrome.	listPallindrome.cpp
Insert data in a sorted linked list.	insertInASortedLinkedList.cpp
Determine the intersection(merging) point of two given linked list.	findIntersectionPointOfLists.cpp, intersection_of_lists.py
Clone a linkedlist which has next and an random pointer, Space Complexity - O(1).	cloneListWithRandomPtr.cpp, clone_list_with_random_ptr.py
Given a sorted linked list with duplicates, remove duplicates in one iteration.	removeDuplicatesFromSortedList.cpp
Using Floyd's cycle finding algorithm, detect if a linkedlist contain cycle, if it does contain cycle, remove the loop	floyedCycleDetection.cpp
Sort a linked list using merge sort	merge_sort.cpp
Given a singly linked list L0 -> L1 -> … -> Ln-1 -> Ln. Rearrange the nodes in the list (in place) so that the new formed list is : L0 -> Ln -> L1 -> Ln-1 -> L2 -> Ln-2 ....	rearrange_list.cpp

Include

Include contains single header implementation of data structures and some algorithms.

Data Structure/Algorithm	Implementation
Generic Macros and Algorithms like swap, random number generation	generic.h
Generic Stack Implementation	stack.h
Generic Queue Implementation	queue.h
Generic List Implementation	list.h
Binary Search Tree Implementation	binarySearchTree.h
Quick Sort Implementation	quickSort.h
Merge Sort Implementation	mergeSort.h
Selection Sort Implementation	selectionSort.h
Bubble Sort Implementation	bubbleSort.h
Linux Kernel Double LinkedList Implementation	double_linked_list.h
Generic Graph Implementation (Adjacency List)	graph.h
Heap Sort Implementation	heap_sort.h
My own string library implementation	pstring.h pstring.cpp

Bit Manipulation Problems

Problem	Solution
Determine if a number is a power of 2.	power_of_2.cpp
Add two binary number represented as string.	addBin.cpp
Determine the next power of 2 for a given number.	next_power_of_2.cpp
Using bit manipulation determine if a number is multiple of 3.	multiple_of_3.cpp
Determine endianess of the machine, print a number in reverse Endianess.	reverseEndianness.cpp
Find the parity of given number.	find_parity.cpp
Implement fast multiplication of a number to 7 using bit manipulation.	multiply_by_7.cpp
Reverse bits of unsigned integer (two methods - Reversing bit by bit & divide and conquer).	reverseBitsOfAnInteger.cpp
Small function to determine position of right most set bit in a given integer.	right_most_set_bit.cpp
Given a vector of numbers, only one number occurs odd number of times, find the number.	find_odd_one_out.cpp
Given two integers, determine if their sum would be interger overflow.	integerOverflow.cpp

Cracking the coding interview problems

Problem	Solution
Problem 1-1 : Edition 6: Write an algorithm to determine whether a string has unique characters or not. Can we do it without using additional data structures?	1-1-hasUniqueChars.cpp, 1-1-hasUniqueChars.py
Problem 1-2 : Edition 5: Reverse a string when you are a pass a null terminated C string.	1-2-edi5-reverseString.cpp
Problem 1-2 : Edition 6: Given two strings, determine if one is permutation of other.	1-2-perm-strings.cpp, 1-2-perm-strings.py
Problem 1-3 : Edition 5: Write an algorithm to remove duplicate chars from a string.	1-3-edi5-removeDuplicates.cpp
Problem 1-3 : Edition 6: URLify: Replace all the spaces in a string with '%20'. Preferebly Inplace	1-3-URLify.cpp
Problem 1-4 : Edition 6: Given a string, write a function to check if it is a permutation of a pallindrome.	1-4-pallindrome-permutations.cpp
Problem 1-5 : Edition 6: There are three possible edits that can be performed on a string - Insert a char, Delete a char, Replace a char. Given two strings, determine if they are one or 0 edit away.	1-5-one-edit-away.cpp
Problem 1-6: Implement a method to perform basic string compression. Example string aabcccccaaa should be compressed to , however if compressed string is bigger than original string, return original string