Pairwise Swap Nodes of a given linked list by changing links
Last Updated :
23 Jul, 2025
Given a singly linked list, write a function to swap elements pairwise. For example, if the linked list is 1->2->3->4->5->6->7 then the function should change it to 2->1->4->3->6->5->7, and if the linked list is 1->2->3->4->5->6 then the function should change it to 2->1->4->3->6->5
This problem has been discussed here. The solution provided there swaps data of nodes. If data contains many fields, there will be many swap operations. So changing links is a better idea in general. Following is the implementation that changes links instead of swapping data.
Implementation:
C++
/* This program swaps the nodes of
linked list rather than swapping the
field from the nodes.
Imagine a case where a node contains
many fields, there will be plenty
of unnecessary swap calls. */
#include <bits/stdc++.h>
using namespace std;
/* A linked list node */
class node {
public:
int data;
node* next;
};
/* Function to pairwise swap elements
of a linked list. It returns head of
the modified list, so return value
of this node must be assigned */
node* pairWiseSwap(node* head)
{
// If linked list is empty or
// there is only one node in list
if (head == NULL || head->next == NULL)
return head;
// Initialize previous and current pointers
node* prev = head;
node* curr = head->next;
head = curr; // Change head before proceeding
// Traverse the list
while (true) {
node* next = curr->next;
curr->next = prev; // Change next of
// current as previous node
// If next NULL or next is the last node
if (next == NULL || next->next == NULL) {
prev->next = next;
break;
}
// Change next of previous to next of next
prev->next = next->next;
// Update previous and curr
prev = next;
curr = prev->next;
}
return head;
}
/* Function to add a node at
the beginning of Linked List */
void push(node** head_ref, int new_data)
{
/* allocate node */
node* new_node = new node();
/* put in the data */
new_node->data = new_data;
/* link the old list of the new node */
new_node->next = (*head_ref);
/* move the head to point to the new node */
(*head_ref) = new_node;
}
/* Function to print nodes
in a given linked list */
void printList(node* node)
{
while (node != NULL) {
cout << node->data << " ";
node = node->next;
}
}
/* Driver code */
int main()
{
node* start = NULL;
/* The constructed linked list is:
1->2->3->4->5->6->7 */
push(&start, 7);
push(&start, 6);
push(&start, 5);
push(&start, 4);
push(&start, 3);
push(&start, 2);
push(&start, 1);
cout << "Linked list before "
<< "calling pairWiseSwap() ";
printList(start);
start = pairWiseSwap(start); // NOTE THIS CHANGE
cout << "\nLinked list after calling"
<< "pairWiseSwap() ";
printList(start);
return 0;
}
// This code is contributed by Manoj N
/* This program swaps the nodes of linked list rather than swapping the
field from the nodes.
Imagine a case where a node contains many fields, there will be plenty
of unnecessary swap calls. */
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
/* A linked list node */
struct Node {
int data;
struct Node* next;
};
/* Function to pairwise swap elements of a linked list */
void pairWiseSwap(struct Node** head)
{
// If linked list is empty or there is only one node in list
if (*head == NULL || (*head)->next == NULL)
return;
// Initialize previous and current pointers
struct Node* prev = *head;
struct Node* curr = (*head)->next;
*head = curr; // Change head before proceeding
// Traverse the list
while (true) {
struct Node* next = curr->next;
curr->next = prev; // Change next of current as previous node
// If next NULL or next is the last node
if (next == NULL || next->next == NULL) {
prev->next = next;
break;
}
// Change next of previous to next next
prev->next = next->next;
// Update previous and curr
prev = next;
curr = prev->next;
}
}
/* Function to add a node at the beginning of Linked List */
void push(struct Node** head_ref, int new_data)
{
/* allocate node */
struct Node* new_node = (struct Node*)malloc(sizeof(struct Node));
/* put in the data */
new_node->data = new_data;
/* link the old list of the new node */
new_node->next = (*head_ref);
/* move the head to point to the new node */
(*head_ref) = new_node;
}
/* Function to print nodes in a given linked list */
void printList(struct Node* node)
{
while (node != NULL) {
printf("%d ", node->data);
node = node->next;
}
}
/* Driver program to test above function */
int main()
{
struct Node* start = NULL;
/* The constructed linked list is:
1->2->3->4->5->6->7 */
push(&start, 7);
push(&start, 6);
push(&start, 5);
push(&start, 4);
push(&start, 3);
push(&start, 2);
push(&start, 1);
printf("\n Linked list before calling pairWiseSwap() ");
printList(start);
pairWiseSwap(&start);
printf("\n Linked list after calling pairWiseSwap() ");
printList(start);
getchar();
return 0;
}
// Java program to swap elements of linked list by changing links
class LinkedList {
static Node head;
static class Node {
int data;
Node next;
Node(int d)
{
data = d;
next = null;
}
}
/* Function to pairwise swap elements of a linked list */
Node pairWiseSwap(Node node)
{
// If linked list is empty or there is only one node in list
if (node == null || node.next == null) {
return node;
}
// Initialize previous and current pointers
Node prev = node;
Node curr = node.next;
node = curr; // Change head before proceeding
// Traverse the list
while (true) {
Node next = curr.next;
curr.next = prev; // Change next of current as previous node
// If next NULL or next is the last node
if (next == null || next.next == null) {
prev.next = next;
break;
}
// Change next of previous to next next
prev.next = next.next;
// Update previous and curr
prev = next;
curr = prev.next;
}
return node;
}
/* Function to print nodes in a given linked list */
void printList(Node node)
{
while (node != null) {
System.out.print(node.data + " ");
node = node.next;
}
}
// Driver program to test above functions
public static void main(String[] args)
{
/* The constructed linked list is:
1->2->3->4->5->6->7 */
LinkedList list = new LinkedList();
list.head = new Node(1);
list.head.next = new Node(2);
list.head.next.next = new Node(3);
list.head.next.next.next = new Node(4);
list.head.next.next.next.next = new Node(5);
list.head.next.next.next.next.next = new Node(6);
list.head.next.next.next.next.next.next = new Node(7);
System.out.println("Linked list before calling pairwiseSwap() ");
list.printList(head);
Node st = list.pairWiseSwap(head);
System.out.println("");
System.out.println("Linked list after calling pairwiseSwap() ");
list.printList(st);
System.out.println("");
}
}
// This code has been contributed by Mayank Jaiswal
# Python3 program to swap elements of
# linked list by changing links
# Linked List Node
class Node:
def __init__(self, data):
self.data = data
self.next = None
# Create and Handle list operations
class LinkedList:
def __init__(self):
# Head of list
self.head = None
# Add data to list
def addToList(self, data):
newNode = Node(data)
if self.head is None:
self.head = newNode
return
last = self.head
while last.next:
last = last.next
last.next = newNode
# Function to print nodes
# in a given linked list
def __str__(self):
linkedListStr = ""
temp = self.head
while temp:
linkedListStr = (linkedListStr +
str(temp.data) + " ")
temp = temp.next
return linkedListStr
# Function to pairwise swap elements
# of a linked list. It returns head of
# the modified list, so return value
# of this node must be assigned
def pairWiseSwap(self):
# If list is empty or with one node
if (self.head is None or
self.head.next is None):
return
# Initialize previous and current pointers
prevNode = self.head
currNode = self.head.next
# Change head node
self.head = currNode
# Traverse the list
while True:
nextNode = currNode.next
# Change next of current
# node to previous node
currNode.next = prevNode
# If next node is the last node
if nextNode.next is None:
prevNode.next = nextNode
break
# Change next of previous to
# next of next
prevNode.next = nextNode.next
# Update previous and current nodes
prevNode = nextNode
currNode = prevNode.next
# Driver Code
linkedList = LinkedList()
linkedList.addToList(1)
linkedList.addToList(2)
linkedList.addToList(3)
linkedList.addToList(4)
linkedList.addToList(5)
linkedList.addToList(6)
linkedList.addToList(7)
print("Linked list before calling"
"pairwiseSwap() ",
linkedList)
linkedList.pairWiseSwap()
print("Linked list after calling "
"pairwiseSwap() ",
linkedList)
# This code is contributed by AmiyaRanjanRout
// C# program to swap elements of
// linked list by changing links
using System;
public class LinkedList {
Node head;
public class Node {
public int data;
public Node next;
public Node(int d)
{
data = d;
next = null;
}
}
/* Function to pairwise swap
elements of a linked list */
Node pairWiseSwap(Node node)
{
// If linked list is empty or there
// is only one node in list
if (node == null || node.next == null) {
return node;
}
// Initialize previous and current pointers
Node prev = node;
Node curr = node.next;
// Change head before proceeding
node = curr;
// Traverse the list
while (true) {
Node next = curr.next;
// Change next of current as previous node
curr.next = prev;
// If next NULL or next is the last node
if (next == null || next.next == null) {
prev.next = next;
break;
}
// Change next of previous to next of next
prev.next = next.next;
// Update previous and curr
prev = next;
curr = prev.next;
}
return node;
}
/* Function to print nodes
in a given linked list */
void printList(Node node)
{
while (node != null) {
Console.Write(node.data + " ");
node = node.next;
}
}
// Driver code
public static void Main(String[] args)
{
/* The constructed linked list is:
1->2->3->4->5->6->7 */
LinkedList list = new LinkedList();
list.head = new Node(1);
list.head.next = new Node(2);
list.head.next.next = new Node(3);
list.head.next.next.next = new Node(4);
list.head.next.next.next.next = new Node(5);
list.head.next.next.next.next.next = new Node(6);
list.head.next.next.next.next.next.next = new Node(7);
Console.WriteLine("Linked list before calling pairwiseSwap() ");
list.printList(list.head);
Node st = list.pairWiseSwap(list.head);
Console.WriteLine("");
Console.WriteLine("Linked list after calling pairwiseSwap() ");
list.printList(st);
Console.WriteLine("");
}
}
// This code contributed by Rajput-Ji
<script>
// javascript program to swap elements of linked list by changing links
var head;
class Node {
constructor(val) {
this.data = val;
this.next = null;
}
}
/* Function to pairwise swap elements of a linked list */
function pairWiseSwap(node) {
// If linked list is empty or there is only one node in list
if (node == null || node.next == null) {
return node;
}
// Initialize previous and current pointers
var prev = node;
var curr = node.next;
node = curr; // Change head before proceeding
// Traverse the list
while (true) {
var next = curr.next;
curr.next = prev; // Change next of current as previous node
// If next NULL or next is the last node
if (next == null || next.next == null) {
prev.next = next;
break;
}
// Change next of previous to next next
prev.next = next.next;
// Update previous and curr
prev = next;
curr = prev.next;
}
return node;
}
/* Function to print nodes in a given linked list */
function printList(node) {
while (node != null) {
document.write(node.data + " ");
node = node.next;
}
}
// Driver program to test above functions
/*
* The constructed linked list is: 1->2->3->4->5->6->7
*/
head = new Node(1);
head.next = new Node(2);
head.next.next = new Node(3);
head.next.next.next = new Node(4);
head.next.next.next.next = new Node(5);
head.next.next.next.next.next = new Node(6);
head.next.next.next.next.next.next = new Node(7);
document.write("Linked list before calling pairwiseSwap() ");
printList(head);
var st = pairWiseSwap(head);
document.write("<br/>");
document.write("Linked list after calling pairwiseSwap() ");
printList(st);
document.write("");
// This code contributed by aashish1995
</script>
OutputLinked list before calling pairWiseSwap() 1 2 3 4 5 6 7
Linked list after callingpairWiseSwap() 2 1 4 3 6 5 7
Time Complexity: The time complexity of the above program is O(n) where n is the number of nodes in a given linked list. The while loop does a traversal of the given linked list.
Auxiliary Space: O(1) since using constant space to track prev and next
Following is the recursive implementation of the same approach. We change the first two nodes and recur for the remaining list. Thanks to geek and omer salem for suggesting this method.
Implementation:
C++
/* This program swaps the nodes of linked list rather than swapping the
field from the nodes.
Imagine a case where a node contains many fields, there will be plenty
of unnecessary swap calls. */
#include <bits/stdc++.h>
using namespace std;
/* A linked list node */
class node {
public:
int data;
node* next;
};
/* Function to pairwise swap elements of a linked list.
It returns head of the modified list, so return value
of this node must be assigned */
node* pairWiseSwap(node* head)
{
// Base Case: The list is empty or has only one node
if (head == NULL || head->next == NULL)
return head;
// Store head of list after two nodes
node* remaining = head->next->next;
// Change head
node* newhead = head->next;
// Change next of second node
head->next->next = head;
// Recur for remaining list and change next of head
head->next = pairWiseSwap(remaining);
// Return new head of modified list
return newhead;
}
/* Function to add a node at the beginning of Linked List */
void push(node** head_ref, int new_data)
{
/* allocate node */
node* new_node = new node();
/* put in the data */
new_node->data = new_data;
/* link the old list of the new node */
new_node->next = (*head_ref);
/* move the head to point to the new node */
(*head_ref) = new_node;
}
/* Function to print nodes in a given linked list */
void printList(node* node)
{
while (node != NULL) {
cout << node->data << " ";
node = node->next;
}
}
/* Driver program to test above function */
int main()
{
node* start = NULL;
/* The constructed linked list is:
1->2->3->4->5->6->7 */
push(&start, 7);
push(&start, 6);
push(&start, 5);
push(&start, 4);
push(&start, 3);
push(&start, 2);
push(&start, 1);
cout << "Linked list before calling pairWiseSwap() ";
printList(start);
start = pairWiseSwap(start); // NOTE THIS CHANGE
cout << "\nLinked list after calling pairWiseSwap() ";
printList(start);
return 0;
}
// This is code is contributed by rathbhupendra
/* This program swaps the nodes of linked list rather than swapping the
field from the nodes.
Imagine a case where a node contains many fields, there will be plenty
of unnecessary swap calls. */
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
/* A linked list node */
struct node {
int data;
struct node* next;
};
/* Function to pairwise swap elements of a linked list.
It returns head of the modified list, so return value
of this node must be assigned */
struct node* pairWiseSwap(struct node* head)
{
// Base Case: The list is empty or has only one node
if (head == NULL || head->next == NULL)
return head;
// Store head of list after two nodes
struct node* remaining = head->next->next;
// Change head
struct node* newhead = head->next;
// Change next of second node
head->next->next = head;
// Recur for remaining list and change next of head
head->next = pairWiseSwap(remaining);
// Return new head of modified list
return newhead;
}
/* Function to add a node at the beginning of Linked List */
void push(struct node** head_ref, int new_data)
{
/* allocate node */
struct node* new_node = (struct node*)malloc(sizeof(struct node));
/* put in the data */
new_node->data = new_data;
/* link the old list of the new node */
new_node->next = (*head_ref);
/* move the head to point to the new node */
(*head_ref) = new_node;
}
/* Function to print nodes in a given linked list */
void printList(struct node* node)
{
while (node != NULL) {
printf("%d ", node->data);
node = node->next;
}
}
/* Driver program to test above function */
int main()
{
struct node* start = NULL;
/* The constructed linked list is:
1->2->3->4->5->6->7 */
push(&start, 7);
push(&start, 6);
push(&start, 5);
push(&start, 4);
push(&start, 3);
push(&start, 2);
push(&start, 1);
printf("\n Linked list before calling pairWiseSwap() ");
printList(start);
start = pairWiseSwap(start); // NOTE THIS CHANGE
printf("\n Linked list after calling pairWiseSwap() ");
printList(start);
return 0;
}
// Java program to swap elements of linked list by changing links
class LinkedList {
static Node head;
static class Node {
int data;
Node next;
Node(int d)
{
data = d;
next = null;
}
}
/* Function to pairwise swap elements of a linked list.
It returns head of the modified list, so return value
of this node must be assigned */
Node pairWiseSwap(Node node)
{
// Base Case: The list is empty or has only one node
if (node == null || node.next == null) {
return node;
}
// Store head of list after two nodes
Node remaining = node.next.next;
// Change head
Node newhead = node.next;
// Change next of second node
node.next.next = node;
// Recur for remaining list and change next of head
node.next = pairWiseSwap(remaining);
// Return new head of modified list
return newhead;
}
/* Function to print nodes in a given linked list */
void printList(Node node)
{
while (node != null) {
System.out.print(node.data + " ");
node = node.next;
}
}
// Driver program to test above functions
public static void main(String[] args)
{
/* The constructed linked list is:
1->2->3->4->5->6->7 */
LinkedList list = new LinkedList();
list.head = new Node(1);
list.head.next = new Node(2);
list.head.next.next = new Node(3);
list.head.next.next.next = new Node(4);
list.head.next.next.next.next = new Node(5);
list.head.next.next.next.next.next = new Node(6);
list.head.next.next.next.next.next.next = new Node(7);
System.out.println("Linked list before calling pairwiseSwap() ");
list.printList(head);
head = list.pairWiseSwap(head);
System.out.println("");
System.out.println("Linked list after calling pairwiseSwap() ");
list.printList(head);
System.out.println("");
}
}
# Python3 program to pairwise swap
# linked list using recursive method
# Linked List Node
class Node:
def __init__(self, data):
self.data = data
self.next = None
# Create and Handle list operations
class LinkedList:
def __init__(self):
# Head of list
self.head = None
# Add data to list
def addToList(self, data):
newNode = Node(data)
if self.head is None:
self.head = newNode
return
last = self.head
while last.next:
last = last.next
last.next = newNode
# Function to print nodes in
# a given linked list
def __str__(self):
linkedListStr = ""
temp = self.head
while temp:
linkedListStr = (linkedListStr +
str(temp.data) + " ")
temp = temp.next
return linkedListStr
# Function to pairwise swap elements of
# a linked list.It returns head of the
# modified list, so return value
# of this node must be assigned
def pairWiseSwap(self, node):
# If list is empty or with one node
if node is None or node.next is None:
return node
# Store head of list after 2 nodes
remaining = node.next.next
# Change head
newHead = node.next
# Change next to second node
node.next.next = node
# Recur for remaining list and
# change next of head
node.next = self.pairWiseSwap(remaining)
# Return new head of modified list
return newHead
# Driver Code
linkedList = LinkedList()
linkedList.addToList(1)
linkedList.addToList(2)
linkedList.addToList(3)
linkedList.addToList(4)
linkedList.addToList(5)
linkedList.addToList(6)
linkedList.addToList(7)
print("Linked list before calling "
"pairwiseSwap() ", linkedList)
linkedList.head = linkedList.pairWiseSwap(
linkedList.head)
print("Linked list after calling "
"pairwiseSwap() ", linkedList)
# This code is contributed by AmiyaRanjanRout
// C# program to swap elements
// of linked list by changing links
using System;
public class LinkedList {
Node head;
class Node {
public int data;
public Node next;
public Node(int d)
{
data = d;
next = null;
}
}
/* Function to pairwise swap
elements of a linked list.
It returns head of the modified
list, so return value of this
node must be assigned */
Node pairWiseSwap(Node node)
{
// Base Case: The list is empty
// or has only one node
if (node == null || node.next == null) {
return node;
}
// Store head of list after two nodes
Node remaining = node.next.next;
// Change head
Node newhead = node.next;
// Change next of second node
node.next.next = node;
// Recur for remaining list
// and change next of head
node.next = pairWiseSwap(remaining);
// Return new head of modified list
return newhead;
}
/* Function to print nodes in a given linked list */
void printList(Node node)
{
while (node != null) {
Console.Write(node.data + " ");
node = node.next;
}
}
// Driver program to test above functions
public static void Main()
{
/* The constructed linked list is:
1->2->3->4->5->6->7 */
LinkedList list = new LinkedList();
list.head = new Node(1);
list.head.next = new Node(2);
list.head.next.next = new Node(3);
list.head.next.next.next = new Node(4);
list.head.next.next.next.next = new Node(5);
list.head.next.next.next.next.next = new Node(6);
list.head.next.next.next.next.next.next = new Node(7);
Console.WriteLine("Linked list before calling pairwiseSwap() ");
list.printList(list.head);
list.head = list.pairWiseSwap(list.head);
Console.WriteLine("");
Console.WriteLine("Linked list after calling pairwiseSwap() ");
list.printList(list.head);
Console.WriteLine("");
}
}
// This code is contributed by PrinciRaj1992
<script>
// javascript program to swap elements of linked list by changing links
var head;
class Node {
constructor(val) {
this.data = val;
this.next = null;
}
}
/*
* Function to pairwise swap elements of a linked It returns head of the
* modified list, so return value of this node must be assigned
*/
function pairWiseSwap(node) {
// Base Case: The list is empty or has only one node
if (node == null || node.next == null) {
return node;
}
// Store head of list after two nodes
var remaining = node.next.next;
// Change head
var newhead = node.next;
// Change next of second node
node.next.next = node;
// Recur for remaining list and change next of head
node.next = pairWiseSwap(remaining);
// Return new head of modified list
return newhead;
}
/* Function to print nodes in a given linked list */
function printList(node) {
while (node != null) {
document.write(node.data + " ");
node = node.next;
}
}
// Driver program to test above functions
/*
* The constructed linked list is: 1->2->3->4->5->6->7
*/
head = new Node(1);
head.next = new Node(2);
head.next.next = new Node(3);
head.next.next.next = new Node(4);
head.next.next.next.next = new Node(5);
head.next.next.next.next.next = new Node(6);
head.next.next.next.next.next.next = new Node(7);
document.write("Linked list before calling pairwiseSwap() ");
printList(head);
head = pairWiseSwap(head);
document.write("<br/>");
document.write("Linked list after calling pairwiseSwap() ");
printList(head);
document.write("");
// This code contributed by umadevi9616
</script>
OutputLinked list before calling pairWiseSwap() 1 2 3 4 5 6 7
Linked list after calling pairWiseSwap() 2 1 4 3 6 5 7
Time Complexity: O(n)
Auxiliary Space: O(n)
Pairwise swap adjacent nodes of a linked list by changing pointers | Set 2
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Array Data StructureIn this article, we introduce array, implementation in different popular languages, its basic operations and commonly seen problems / interview questions. An array stores items (in case of C/C++ and Java Primitive Arrays) or their references (in case of Python, JS, Java Non-Primitive) at contiguous
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String in Data StructureA string is a sequence of characters. The following facts make string an interesting data structure.Small set of elements. Unlike normal array, strings typically have smaller set of items. For example, lowercase English alphabet has only 26 characters. ASCII has only 256 characters.Strings are immut
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Hashing in Data StructureHashing is a technique used in data structures that efficiently stores and retrieves data in a way that allows for quick access. Hashing involves mapping data to a specific index in a hash table (an array of items) using a hash function. It enables fast retrieval of information based on its key. The
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Linked List Data StructureA linked list is a fundamental data structure in computer science. It mainly allows efficient insertion and deletion operations compared to arrays. Like arrays, it is also used to implement other data structures like stack, queue and deque. Here’s the comparison of Linked List vs Arrays Linked List:
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Stack Data StructureA Stack is a linear data structure that follows a particular order in which the operations are performed. The order may be LIFO(Last In First Out) or FILO(First In Last Out). LIFO implies that the element that is inserted last, comes out first and FILO implies that the element that is inserted first
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Queue Data StructureA Queue Data Structure is a fundamental concept in computer science used for storing and managing data in a specific order. It follows the principle of "First in, First out" (FIFO), where the first element added to the queue is the first one to be removed. It is used as a buffer in computer systems
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Tree Data StructureTree Data Structure is a non-linear data structure in which a collection of elements known as nodes are connected to each other via edges such that there exists exactly one path between any two nodes. Types of TreeBinary Tree : Every node has at most two childrenTernary Tree : Every node has at most
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Graph Data StructureGraph Data Structure is a collection of nodes connected by edges. It's used to represent relationships between different entities. If you are looking for topic-wise list of problems on different topics like DFS, BFS, Topological Sort, Shortest Path, etc., please refer to Graph Algorithms. Basics of
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Trie Data StructureThe Trie data structure is a tree-like structure used for storing a dynamic set of strings. It allows for efficient retrieval and storage of keys, making it highly effective in handling large datasets. Trie supports operations such as insertion, search, deletion of keys, and prefix searches. In this
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Algorithms
Searching AlgorithmsSearching algorithms are essential tools in computer science used to locate specific items within a collection of data. In this tutorial, we are mainly going to focus upon searching in an array. When we search an item in an array, there are two most common algorithms used based on the type of input
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Sorting AlgorithmsA Sorting Algorithm is used to rearrange a given array or list of elements in an order. For example, a given array [10, 20, 5, 2] becomes [2, 5, 10, 20] after sorting in increasing order and becomes [20, 10, 5, 2] after sorting in decreasing order. There exist different sorting algorithms for differ
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Introduction to RecursionThe process in which a function calls itself directly or indirectly is called recursion and the corresponding function is called a recursive function. A recursive algorithm takes one step toward solution and then recursively call itself to further move. The algorithm stops once we reach the solution
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Greedy AlgorithmsGreedy algorithms are a class of algorithms that make locally optimal choices at each step with the hope of finding a global optimum solution. At every step of the algorithm, we make a choice that looks the best at the moment. To make the choice, we sometimes sort the array so that we can always get
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Graph AlgorithmsGraph is a non-linear data structure like tree data structure. The limitation of tree is, it can only represent hierarchical data. For situations where nodes or vertices are randomly connected with each other other, we use Graph. Example situations where we use graph data structure are, a social net
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Dynamic Programming or DPDynamic Programming is an algorithmic technique with the following properties.It is mainly an optimization over plain recursion. Wherever we see a recursive solution that has repeated calls for the same inputs, we can optimize it using Dynamic Programming. The idea is to simply store the results of
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Bitwise AlgorithmsBitwise algorithms in Data Structures and Algorithms (DSA) involve manipulating individual bits of binary representations of numbers to perform operations efficiently. These algorithms utilize bitwise operators like AND, OR, XOR, NOT, Left Shift, and Right Shift.BasicsIntroduction to Bitwise Algorit
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Advanced
Segment TreeSegment Tree is a data structure that allows efficient querying and updating of intervals or segments of an array. It is particularly useful for problems involving range queries, such as finding the sum, minimum, maximum, or any other operation over a specific range of elements in an array. The tree
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Pattern SearchingPattern searching algorithms are essential tools in computer science and data processing. These algorithms are designed to efficiently find a particular pattern within a larger set of data. Patten SearchingImportant Pattern Searching Algorithms:Naive String Matching : A Simple Algorithm that works i
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GeometryGeometry is a branch of mathematics that studies the properties, measurements, and relationships of points, lines, angles, surfaces, and solids. From basic lines and angles to complex structures, it helps us understand the world around us.Geometry for Students and BeginnersThis section covers key br
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