ARRAY IN

C++

Introduction to Array

Need of Array

Types of Array Single dimensional Two dimensional Multi dimensional

Array initialization

Unsized Array initialization

String as an array

Contents

Array is a collection of variables that can hold value of same type and reference by common name .Its is a derived data Structure

Array are always stored in a continuous memory locations.An Array either be a integer ,character, or float base type (Data type of array) .

Array indexing is always start from zero and highest address corresponds to last element

Introduction

Num [0]

Num[1]

Num[2]

Num[3]

Num[4]

Num[5]

Int num [6]

Base type of arrray

Name of array

Size of array

Continuous memory

allocation of array

To store processed large number of variables of same data type and reference/nameEasy understanding of programExample: Marks 0 1

2 3 4 5

Need of Arrray

One dimensional Two dimensional Multi dimensional

Types of Array

A one dimensional array is one in which one subscript /indices specification is needed to specify a particular element of array

Declaration :Data_type array_name [size of array ];

Eg:Int num[10];

1-D Array

num[0] num[1] num[2] num[3] num[4] num[5] num[6] num[7] num[8] num[9]

2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 starting Address of location

Total memory in bytes that an array is occupied :

Size of array=size of array*size of(base type) Hear, 10*2=20 

39 56 23 98 6 56 09 2 54 67

Memory representation:

A 2-d array is an array in which each element is itself an array i.e int num[4][3] 0 1 2 0 1 2 3

2-D Array

No of rows

No of colum

ns

Num [2][1]No of element in 2-D array =M*N

Total bytes= no of rows*no of columns*size of(base type) Memory reprsentation in 2-D array: char A [2][3] A[0][0] A[0][1] A[0][2] A[1][0] A[1][1] A[1][2]

5001 5002 5003 5004 5005 5006

size of 2-D array

An array with dimensions more than two .The maximum limit of array is compiler dependent

Declration:Data_type name [a][b][c][d][e][f]…….[n];

Array of 3 or more dimensional are not often use because of huge memory requirement and complexity involved

Multi dimensional array

C++ provides the facility of array initialization at the time of declaration .General form of array initialization is as:Type array_name[size 1]…..[size N] ={vale list};

Eg:Int days_month[12]={31,25,29,03,31,19,20,31,18,20,31,29};

Char string[6]={‘a’,’r’,’g’,’y’,’d’,’\0’};

2-D array are also initialized in same way as linear array Int cube[4][2]={ 1,3,

4,6, 9,37, 5,78 };

Array initialization

C++ allowed you to skip the size of array in an array initialization statement C++ automatically create an array big enough to hold all the initializers presentChar S1[] =“ first string ”;

you skip the size, you must give list of initializers so that C++ can calculate the size of array Int val []={3,5,6,2,8,9,6,4};Int cube [] [2] ={ 1,3, 67,7, 6,87, };

Unsized array initializations

C++ does not have a String data type ,it impairments string as 1-D character Arrray .A string as a character array is terminate by a null character ‘\0’

Char str 1 [11];

Char square [][]={ ‘first string’, ‘second string’, ‘third string’

};

String as array

Thank you