Data structures-1

Data structures:
->Data structures are ways of organizing and storing data in a computer so that it can be accessed and modified efficiently. They are fundamental to computer science and are used in various applications to manage and process data.

Arrays:
->An array is a collection of elements, with each element in the array having an index value that starts from 0 and goes up to
n−1, where 𝑛 is the total number of elements in the array.

Example:
Imagine a passenger train that has a fixed number of compartments, say 5 compartments. Each compartment can hold a certain number of passengers.

Arrangement of Compartments:
1.The compartments are numbered from 0 to 4 (for a total of 5 compartments).
2.You can think of the compartments as an array, where each index represents a compartment number.

The arrangement looks like this:

Compartment 0: Empty
Compartment 1: Empty
Compartment 2: Empty
Compartment 3: Empty
Compartment 4: Empty

Boarding the Train:
1.Passengers A, B, and C enter Compartment 0.
2.Passengers D and E enter Compartment 1.
3.Passenger F enters Compartment 2.

Now the arrangement of the compartments looks like this:

Compartment 0: Passenger A, Passenger B, Passenger C
Compartment 1: Passenger D, Passenger E
Compartment 2: Passenger F
Compartment 3: Empty
Compartment 4: Empty

Unloading Passengers:
1.When the train reaches its destination, Passengers A, B, and C get off from Compartment 0. After this, the compartments look like this:

Compartment 0: Empty
Compartment 1: Passenger D, Passenger E
Compartment 2: Passenger F
Compartment 3: Empty
Compartment 4: Empty

Stack:
->A stack is a linear data structure that follows the Last In, First Out principle. This means that the last element added to the stack is the first one to be removed.

Example:
simple stack example using bangles in the hand

Pushing a Bangle:
1.You start with an empty hand.
2.You place "Bangle A" on your palm.
3.Next, you add "Bangle B" on top of "Bangle A"
4.Finally, you add "Bangle C" on top of "Bangle B"

Your hand now looks like this

[Bangle C]
[Bangle B]
[Bangle A]

Popping a Bangle:
1.When you want to remove a bangle, you take "Bangle C" off the top of the stack.

Your hand now looks like this:

[Bangle B]
[Bangle A]

Queue:
->A queue is a linear data structure that follows the First In, First Out principle. This means that the first element added to the queue is the first one to be removed, similar to a line of people waiting for service.

Example:
Imagine there’s a bookstore with a line of people waiting outside to buy books.

People Arriving:
1.Person A arrives first and stands at the front of the line.
2.Then, Person B arrives and stands behind Person A.
3.Next, Person C arrives and stands behind Person B.

The line now looks like this:

Front -> Person A
         Person B
         Person C <- Rear

Serving Customers:
1.The shop opens, and the cashier starts serving the first person in line.
2.Person A is the first to be served and buys their books. After this, they leave the line

The line now looks like this:

Front -> Person B
         Person C <- Rear