This document discusses arrays in C language. It defines an array as a data structure that stores a collection of similar data types. It describes how to declare, create and initialize single and multi-dimensional arrays in C. It also explains that arrays have a fixed size once declared, and elements can be accessed via indexes. Multidimensional arrays can be thought of as arrays of arrays.

1. Array in C Language

2. Index
Introducing Arrays.
Declaration of a Array. Variables,
Creating Arrays.
The Length of Arrays.
Initializing Arrays.
Multidimensional Arrays.

3. Introducing Arrays
 Array is a data structure that represents a
collection of the same types of data.
int num[10];
Num reference
An Array of 10 Elements
of type int.
num [0]
num[1]
num[2]
num [3]
num[4]
num[5]
num[6]
num[7]
num[8]
num[9]

4. Declaring Array Variables
 Data type array name[index];
Example:
int list[10];
char num[15];
float hat[20];

5. Creating Arrays
 Data type array-name[size];
Example:
int num[10];
num[0]references the first element in
the array.
num[9]references the last element in
the array.

6. The Length of Arrays
 Once an array is created, its size is
fixed. It cannot be changed.
For Example,
int arr[10];
You can not insert any number to arr[11]
location because it is not initialized.

7. Initializing Arrays
 Declaring, creating, initializing in one
step:
int my Array[5] = {1, 2, 3, 4, 5};
int studentAge[4];
studentAge[0] = 14;
studentAge[1] = 13;
studentAge[2] = 15;
studentAge[3] = 16;

8. Multidimensional Arrays
int matrix[10] [10];
for (i=0; i<10; i++)
for (j=0; j<10; j++)
{
matrix[i] [j] = i * j;
}
float mat[5] [5];

9. Multidimensional Array Illustration
0 1 2 3 4
0
1
2
3
4
0 1 2 3 4
0
1
2 7
3
4
int matrix[5] [5]; matrix[2] [1] = 7
0 1 2
0 1 2 3
1 4 5 6
2 7 8 9
3 10 11 12
int[][] array ={
{1, 2, 3},
{4, 5, 6},
{7, 8, 9},
{10, 11, 12}};

10. Initializing of Multidimensional Arrays
To declare, create and initialize a multidimensional
array.
For example,
int[][] array = {
{1, 2, 3},
{4, 5, 6},
{7, 8, 9},
{10, 11, 12}
};
This is equivalent to the following statements:
array[0][0] = 1; array[0][1] = 2; array[0][2] = 3;
array[1][0] = 4; array[1][1] = 5; array[1][2] = 6;
array[2][0] = 7; array[2][1] = 8; array[2][2] = 9;
array[3][0] = 10; array[3][1] = 11; array[3][2] = 12;