# Array Data Structure

**Array Data Structure** is the following article of Introduction to Data Structure in Learning Data Structure Series.

Array is a collection of elements of same type, stored in sequential memory locations. The elements of array are referenced by the index or subscript of array. Array is a linear type of data structure because the memory locations are sequentially allocated to store the data.

**Example**: Suppose there is an array –** Data** – having capacity to store 10 elements then the elements of array will be referred by the index like Data[2] *(read as Data of 2*), Data[7] etc.

Name of Array: **Data**

Index |
0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |

Value |
10 | 15 | 35 | 60 | 45 | 9 | 12 | 80 | 33 |

eg: Data[1] = 15

Index |
0 | 1 |
2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |

Value |
10 | 15 |
2 | 35 | 60 | 45 | 9 | 12 | 80 | 33 |

eg: Data[6] = 9

Index |
0 | 1 | 2 | 3 | 4 | 5 | 6 |
7 | 8 | 9 |

Value |
10 | 15 | 2 | 35 | 60 | 45 | 9 |
12 | 80 | 33 |

There are some types of arrays like one-dimension, two-dimension and multi-dimensional array. Let’s learn it one by one.

## One – Dimensional Array Data Structure:

A linear array with single subscript is known as one-dimensional array. Each element in the array is referenced by a single index or subscript. One-dimensional arrays are frequently used in programming.

Name of Array: **DATA**

Index | 1 | 2 | 3 | 4 | 5 | 6 |

Value | 27 | 14 | 85 | 99 | 101 | 950 |

Above example is of one-dimensional array because every element in the array is denoted by single memory location.

Example: Element 99 here is denoted as DATA[4] and 27 by DATA[1].

DATA[4] = 99

DATA[1] = 27.

## Two – Dimensional Array Data Structure:

An array with two subscripts is known as two-dimensional array. A two dimensional array A is a collection of m*n data elements such that each element is specified by a pair of subscript. The two-dimensional arrays are called as matrices in mathematics and table in business applications.

Example:

In above array, there are two index values: Row index value and column index value. Row is horizontal element and column is vertical element.Fig: Two-dimensional 3*3 array A.

In this ,

A[1,1] means element of array A of 1^{st} row and 1^{st} column

A[3,2] means element of array A of 3^{rd} row and 2^{nd} column

In above example A[3,2] =2

A[2,2] = 25 and

A[1,3] = 7

## Multi – Dimensional Array Data Structure:

An array having more than two subscripts is known as multi-dimensional array. An *n-* dimensional array *B* is a collection of *m _{1}. m_{2}. m_{3}*

**data elements in which each element is specified by a list of n integers such as**

*…. m*_{n }**K**called subscripts, with the property that

_{1, }K_{2}_{, . , . , . ,}K_{n }1 ≤ K_{1 }≤_{ }m_{1 } , 1 ≤ K_{2 }≤ _{ }m_{2 } , . . . , 1 ≤ K_{n }≤_{ }m_{n }

The elements of B with subscript **K _{1, }K_{2}_{, . , . , . ,}K_{n }** will be denoted by B[K

_{1, }K

_{2, . , . , . ,}K

_{n}]

In this article we learnt basics about array data structure and their types. This article follows with the operations like insert & delete elements, sorting, searching and other operations we can perform on arrays. We will learn Insert and Delete Operation on Array in the following article of Learning Data Structure Series.