An array is a collection of similar data types stored in contiguous memory locations that allows storing multiple values in a single variable. Arrays are declared with the data type, array name, and size, and can store data through multiple methods like initializing values or using indexes to access elements. Array indexes start at 0 to represent the first element.

1. LECTURE 1
ARRAYS
Instructor
Muhammad Shahid Mahmood

2. What is an
array?
An array is a collection of similar items
stored in contiguous memory
locations.
Arrays are used to store multiple values
in a single variable, instead of declaring
separate variables for each value.
To store records of 500 students, we
can define an array with size 500 that
can hold the marks of all students.

3. STRUCTURE OF
AN ARRAY

4. Declaration of an Array
◦ To use an array, we must declare it first.
◦ In array declaration, we define the type of array depends on the data going to
store in variables(int, float, char)
◦ Secondly, we use to write name of array, depends on the purpose of arrays being
used
◦ Third, we define the number of elements we are going to store in a specific array.

5. Syntax
◦ The possible syntax to declare array is as follows:
◦ DataType ArrayName [Size of an Array]
◦ We store 500 students name in an array
◦ String Name[500]

6. Storing Data
in Arrays
To store data in arrays we use multiple ways, few of
them are as follows:
Method 1:
int arr[5];
arr[0] = 10;
arr[1] = 20;
arr[2] = 30;
arr[3] = 40;
arr[4] = 50;

7. Accessing
Array
Elements
Array index starts with 0, which means the first array element is at
index 0, second is at index 1 and so on. We can use this information
to display the array elements.
◦ #include <iostream>
◦ using namespace std;
◦ int main(){
◦ int arr[] = {11, 22, 33, 44, 55};
◦ cout<<arr[0]<<endl;
◦ cout<<arr[1]<<endl;
◦ cout<<arr[2]<<endl;
◦ cout<<arr[3]<<endl;
◦ cout<<arr[4]<<endl;
◦ return 0;
◦ }
Output:
11
22
33
44
55