c progrmming(unit-iii)

7/30/2019 c progrmming(unit-III)

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UNIT-III

3.1 arrays- definition, initialization, strings ascharacter arrays, two dimensional andmultidimensional arrays, and variable length arrays.

3.2 pointers- definition, pointer variable, pointer to apointer, memory mapping, arithmetic operations onpointers, relationship between arrays and pointers,pointers as arguments and return type of a function,pointers to a function, array of pointers and pointersto arrays, dynamic memory allocation.

3.3- input output functions, string handling functions.


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Definition of array Array- array is a collection of similar data types stored

contiguously in memory under the same name.

Array- it is a collection of homogeneous elements. HOW TO CREATE AN ARRAY

Before we create an array, we need to decide on twoproperties:

Element type: what kind of data will your array hold?ints, double, chars? Remember, we can only choose one type.

Array size: how many elements will your array contain?

When we initially write our program, we must pick an arraysize. An array will stay this size throughout the execution ofthe program. In other words, we can change the size of anarray at compile time, but cannot change it at run-time.


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USING ARRAYS IN C

In C, the arrays can be classified based on howthe data items are arranged for human

understanding Arrays are broadly classified into three

categories,

1. One dimensional arrays

2. Two dimensional arrays

3. Multi dimensional arrays


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1. ONE DIMENSIONAL ARRAYS

One dimensional array is a linear list consisting of

related and similar data items. In memory all the dataitems are stored in contiguous memory locations one

after the other.

syntax-Datatype array_name[size];

Ex- int a[10];

created an array of 10 integersfloat x[5];

created an array of 5 floating point values

double z[8];

created an array of 8 double values.


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Referencing\ accessing array elements Array elements are accessed with subscript, the

number in the brackets following the array name.

This number specifies the elements position in the

array.

The subscript would be 0,1,...... n-1.


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// C program to read an array elements and

find the sum of the elements.

#include

void main()

{ int a[10];

int i, SIZE, total=0;

printf(\n Enter the size of the array : );

scanf(%d,&size);

for (i = 0; i < SIZE ; i++)

scanf(%d,&a[i]);for (i = 0; i < SIZE ; i++)

total += a[i];

printf("Total of array element values is %d\n", total);

getch();}


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Few important points about the array

1. an array is a collection of similar elements.

2. the first element in the array is numbered

from 0 to n-1.

3. while declaring an array we have to specifytype and size(dimension) of an array to the

compiler.

4. however big an array all the elements are

always stored in contiguous memory location.


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Initializing array elements We have four options for initializing one dimensional arrays.

But, first, REMEMBER THIS: Just like regular variables, arrays that have not been initialized maycontain garbage values.

But, now, the stakes are even higher. If you declare an array with 31 elements, and forget to initialize it,you end up with 31 garbage values!

Option 1 Initializing all memory locations

If you know all the data at compile time, you can specify all your data withinbrackets:

int x [5] = {75, 79, 82, 70, 68};

during compilation, 5 contiguous memory locations are reserved by thecompiler for the variable temp and all these locations are initialized as shownin Fig. If the size of integer is 2 bytes, 10 bytes will be allocated for thevariable temp.

x[0] x[1] x[2] x[3] x [4]

1000 1002 1004 1006 1008 Address

Figure: Storage Representation of array


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Option 2 initialization without size

If we omit the size of your array, but specify an initial

set of data, the compiler will automatically determinethe size of your array. This way is referred as

initialization without size.

int X [] = {75, 79, 82, 70, 68};

the array size will be set of the total number of initialvalues specified.

Here, the compiler creates an array of 5 elements.

x[0] x[1] x[2] x[3] x [4]

1000 1002 1004 1006 1008 Address



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Option 3 Partial Array Initialization

If the number of values to be initialized is less than the size of

the array, then the elements are initialized in the order from 0 th

location. The remaining locations will be initialized to zeroautomatically.

Even though compiler allocates 5 memory locations, using this

declaration statement, the compiler initializes first three

locations with 75,70 and 82,the next set of memory locationsare automatically initialized to 0s by the compiler as shown in

figure

x[0] x[1] x[2] x[3] x [4]

1000 1002 1004 1006 1008 Address



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Option 4

If you do not know any data ahead of time, but you want to

initialize everything to 0, just use 0 within { }.

For example:

int x [5] = {0};

x[0] x[1] x[2] x[3] x [4]

1000 1002 1004 1006 1008 Address


For example:

int x [5] = {5};

x[0] x[1] x[2] x[3] x [4]

1000 1002 1004 1006 1008 Address



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Array of characters(string) In c language array of characters are treated as

character string.

The size in the character array represents themaximum number of characters that the string canhold.

For example: char name[6];

Declares name as an character array (string) that canhold a maximum of 6 characters.

SNIST SN

I

S

T

\0

Whenever compiler find array of

characters , it terminates with the

additional character call it as nullcharacter.

so name[5]- contains the null character.

When declaring character arrays, we

must always use one extra space for the

null character.


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Initialization of character array

char name[]= {s,n,i,s,t,\0};

or char name[]=snist;- in this declaration compilerautomatically inserts the null character.

Bound checking

In c there is no check to see whether the subscriptused for an array exceeds the size of an array or not.

Ex- main()

{

int x[50];for(i=0;i


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TWO DIMENSIONAL ARRAYS

Whenever you want to store the tabular data use the

two dimensional array.

Example- store the student name, rollno, and

attendance.

The data must be in rows and columns.- matrix Declaration of two dimensional array

data type array_name[rows][columns];


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2- dimensional arrays Example

char names[3][4];

in the above declaration

char(dataType) specifies type of element in each slot names(array_name) specifies name of the array

[3](rows) specifies number of rows

[4](cols) specifies number of columns

Initialization of two dimensional arrays

An array may be initialized at the time of declaration:

char names [3][4] = {

{J, 'o', 'h', 'n'},

{M, 'a', 'r', 'y'},

{I, 'v', 'a', 'n'}};

While initializing a 2-d array it is necessary to mention the columndimension. so that compiler automatically arrange the elements in rowsand columns.

Row dimension is optional.

In memory all the elements are stored in row major- format.


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They are stored in memory as

col0 col1 col2

Row0 [0][0] [0][1] [0][2]Row1 [1][0] [1][1] [1][2]

Row2 [2][0] [2][1] [2][2]


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int x[4][3]={{1, 2, 3},

{4, 5, 6},

{7, 8, 9},{10, 11, 12}};

int x[3][2]={1,2,3,4,5,6};

int x[][2]={1,2,3,4,5,6};

int x[2][]={1,2,3,4,5,6};

int x[][]={1,2,3,4,5,6};Never work

Initializing 2D arrays

An array may be initialized at the time of declaration:

I iti li i 2D


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Initializing 2D arrays

char names[3][4] = {

{ 'J', 'o', 'h', 'n'} ,

{ 'M', 'a', 'r', 'y'} ,{ 'I', 'v', 'a', 'n'}

};

An integer array may be initialized to

all zeros as follows:

This only works for zero.

int nums[3][4] = {0};

nums[0][0] = 16;

printf("%d", nums[1][2]); To access an element of a 2Darray, you need to specify both the

row and the column:

'J' 'o' 'h' 'n'

'M' 'a' 'r' 'y'

is stored:

'J'

'o'

'h''n'

'M'

'a'

'r'

'y'

Address

...

4269

4270

42714272

4273

4274

4275

4276...

Two-dimensional arrays in C are stored in "row-major format":the array is laid out contiguously, one row at a time:


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3. Multidimensional array

C allows arrays of three or more dimensions.

Syntax

Data type array_name[size1][size2]..[sizen];

Array declarations should understand from right-to-left

int a[10][3][2];

an array of ten arrays of three arrays of two ints


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int arr[3][4][2] ={

{ { {

{ 2, 4 }, { 7, 6 }, { 8, 9 },

{ 7, 8 }, { 3, 4 }, { 7, 2 },

{ 3, 4 }, { 5, 3 }, { 3, 4 },

{ 5, 6 } { 2, 3 } { 5, 1 }

}, }, }

};

array of three

arrays

Array of 4 rows and 2 columns


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/* write a c program to calculate the addition of two


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/* write a c program to calculate the addition of two

matrices*/

#include

#include

void main()

{int m,n,i,j,a[10][10],b[10][10],c[10][10];

printf("\n enter the size of the matrix\n");

scanf("%d %d", &m,&n);

printf("enter the elements of matrix a\n");

for(i=0;i


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/ Fill 2 d array, print out values, sum the array. /#include #define M 3 /* Number of rows */#define N 4 /* Number of columns */int main(void){

int a [ M ] [ N ], i, j, sum = 0;for ( i = 0; i < M; ++i ) /* fill the array */

for (j = 0; j < N, ++j )a [ i ] [ j ] = i + j;

for ( i = 0; i < M; ++i ){ /* print array values */for (j = 0; j < N, ++j )

printf(a [ %d ] [ %d ] = %d , i, j, a[ i ] [ j ]);printf (\n);}for ( i = 0; i < M; ++i ) /* sum the array */

for (j = 0; j < N, ++j )sum += a[ i ] [ j ];

printf(\nsum = %d\n\n);return 0;} Produces the output:

a[ 0 ] [ 0 ] = 0 a[ 0 ] [ 1 ] = 1 a[ 0 ] [ 2 ] = 2 a[ 0 ] [ 3 ] = 3

a[ 1 ] [ 0 ] = 1 a[ 1 ] [ 1 ] = 2 a[ 1 ] [ 2 ] = 3 a[ 1 ] [ 3 ] = 4

a[ 2 ] [ 0 ] = 0 a[ 2 ] [ 1 ] = 3 a[ 2 ] [ 2 ] = 4 a[ 2 ] [ 3 ] = 5

sum = 30


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Variable length arrays

i


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pointers

Introduction

Pointers are one of the derived types in C. One of the powerfultool and easy to use once they are mastered.

Some of the advantages of pointers are listed below:

A pointer enables us to access a variable that is defined outside

the function. Pointers are more efficient in handling the data tables.

Pointers reduce the length and complexity of a program.

The use of a pointer array to character strings save data storage

space in memory.

The real power of C lies in the proper use of pointers.

As we know computers use their memory for storing the


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As we know, computers use their memory for storing theinstructions of a program, as well as the values of the variablesthat are associated with it.

The computers memory is a sequential collection of storage

cells. Each cell can hold one byte of information, has a unique

number associated with it called as address.

The computer addresses are numbered consecutively, startingfrom zero. The last address depends on the memory size.

Let us assume the size of the memory is 64K then,

The total memory locations = 64K

= 64 * 1K

= 64 * 1024 bytes

= 65536 bytes (locations)

So, here the last address is 65535(started with 0).


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Whenever we declare a variable, the system allocates , anappropriate location to hold the value of the variablesomewhere in the memory,.

Consider the following declaration, int i=10;

This declaration tells the C compiler to perform the followingactivities:

Reserve space in the memory to hold the integer value.

Associate the name i with this memory location.

Store the value 10 at this location.

We can represent is location in the memory by the followingmemory map:

10

i

65524

Variable name

Value at location

Address of variable


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We can print the address through following program.

main()

{int i=10;

printf(address of i=%u,&i);

printf(value of i=%d,i);

}

65524

10

& operator is used to print the address of the variable.

The format specifier of address is %u (unsigned integer),

the reason is addresses are always positive values.

We can also use %x to know the address of a variable.Note - & operator should not be used for the constant

expressions. &125 (Pointing at constant)

int a[10];

&a (pointing to array name)

&(x+y) (pointing at expressions)

Pointer definition


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Pointer- definition

A variable Which holds the address of some other variable is called

pointer variable.

A pointer variable should always contain the address only.

The * Operator (asterisk)

It is called as Value at address operator. It returns the value stored at a

particular address.

It is also Known as Indirection or Dereferencing Operator.

accessing a variable through pointerthe following sequence of operations have to be performed ,to use pointers.

1. Declare an ordinary variable.

2. Declare a pointer variable.

3. Initialize a pointer variable (Provide link between pointer

variable and ordinary variable).

4. Access the value of a variable using pointer variable.

D l i i bl


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Declaring a variable

the syntax for declaring a pointer variable

data type *ptr_name;

This tells the compiler three things about the variable ptr_name.

1. The asterisk(*) tells that the variable ptr_name is a pointer variable.

2.ptr_name needs a memory location.

3.ptr_name points to a variable of type data type.

For example,

int *p;

p is a pointer variable of type integer, which stored the address of the

integer variable. It doesnt mean the p is going to store the integer value


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Initialize a pointer variable

Once a pointer variable has been declared, it can be made topoint to a variable using statement such as

ptr_name=&var;

Which cause ptr_name to point to var.Now ptr_name containsthe address ofvar. This is known as pointer initialization.

Before a pointer is initialized it should not be used.

Access the value of a variable using pointer variable.

*ptr_name


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10 8342

i pi

8342 8338

output

The following code illustrates how to declare int ,char and float pointers.


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The following code illustrates how to declare int ,char and float pointers.

Here we have declared three variables of type int, float and char ,also three

pointer variables points to int, float and char. Remember here pf points to

the value of type float but its type is unsigned integer only

10 15.67Ai c f

6432 4562 8765

P i t t i t


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Pointer to pointer

A variable which contains the address of a pointer variable is

known as pointer to pointer.

Syntax for declaring pointer to pointerdata type **ptr_ptr;

main()

{

int i=100,*j,**k;j=&i;

k=&j;

printf(\n address of i=%u,&i);

printf(\n address of i=%u,j);

printf(\n address of i=%u,*k);

printf(\n address of j=%u,&j);printf(\n address of j =%u,k);

printf(\n address of k=%u,&k);

printf(\n value of i =%d,i);

Printf(\n valude of i=%d,*(&i));

printf(\n value of i=%d,*j);

Printf(\n value of i=%d,**k);}

100 20022000

k

2000 2002 2004

ji


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Lab programs- 22/11/2011

Write a c program for multiplication of two matrices.

Cycle- 7.1 a function that takes an integer n as argumnet andreturn 1 if it is prime number and 0 otherwise.

7.2 a function that takes a real number x and positive integer n

asarguments and return xn 7.3 a function that takes a positive integer n as an argument

and returns the nth fibonacci number

7.4 factorial of a number using recursive and non recursive

functions. 7.5 gcd of two numbers using recursion and non recursion.

7.6 Lcm of two numbers using recursion.

P i t t f ti


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Passing parameters to a function

Parameters to be passed to a function in two ways.

1. call by value

2. call by reference.

1. call by value-

in which values of the actual arguments are copied into the

corresponding formal arguments of the called function. whatever changes made in the formal arguments in the called

function have no effect on the values of the actual arguments.

2. call by reference-

In this method the addresses of the actual arguments in thecalling function are copied into the formal arguments of the

called function.

Whatever changes made in the formal arguments in the called

function can have effect to the value of the actual arguments inthe callin function.

Write a c program to swapping of two numbers using call by


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Write a c program to swapping of two numbers using call by

value and call by reference.Call by value

void swap(int,int);

void main()

{

int a=10,b=20;

swap(a,b);

printf(\n a and b values after swapping);

printf(\na=%d,b=%d,a,b);

}//main

// function definition

swap(int x,int y)

{

int temp;

temp=x;

x=y;y=temp;

printf(\nx=%d,y=%d,x,y);

}//swap()

Call by reference

void swap(int,int);

void main()

{

int a=10,b=20;

swap(&a,&b);

printf(\n and b values after swapping);

printf(\n a=%d b=%d,a,b);

}//main

//function definition

swap(int *x,int *y)

{

int temp;

temp=*x;

*x=*y;*y=temp;

}//swap

W it f ti t t d i f f i l h i


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Write a function to compute are and circumference of a circle, having areaand circumference as pointer arguments and radius as an ordinary argument.

void main()

{int radius;

float area,circum;

printf(\n enter radius of a circle);

scanf(%d,&radius);

areacircum(radius, &area,&circum);

printf(area=%f, area);printf(\n circumference=%f,circum);

}//main

areacircum(int r,float *a, float *c)

{

*a=3.14*r*r;

*c=2*3.14*r;

}

A ith ti ti i t


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Arithmetic operations on pointers

void main()

{

int i=3,*x;

float j=1.5,*y;

char k=c,*z;

x=&i;

y=&j;

z=&k;

printf(\n address in x=%u,x);

printf(\n address in y=%u,y);

printf(\n address in z= %u,z);

x++;

y++;

z++;

printf(\n address in x=%u,x);printf(\n address in y=%u,y);

printf(\n address in z= %u,z);

}

address in x=65524address in y=65520

address in z=65519

Whenever a pointer is incremented

it points to the immediately next location

of its type.When an integer pointer x is incremented

it points to an address two locations after the

current location.

address in x=65526address in y=65524

address in z=65520

If pointer variable is decremented it points to

the earlier locations by its type.

The following operations we can perform on the pointers.


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The following operations we can perform on the pointers.

1. add number to a pointer.

void main()

{ int i=10,*j;

j=&i;

printf(j value=%u,j);

j=j+1;


j=j+3;


2. Subtract a number from a pointer

void main()

{

int i=10,*j;

j=&i;


j=j-1;printf(j value=%u,j);

j=j-3;



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3. Subtraction of one pointer from another pointer

one pointer can be subtracted from the other pointer both

must be point to elements of the same array.

The resultant value would be the number of elements

separating the corresponding array elements.

void main()

{

int a[]={10,20,30,40,50};int *i,*j;

clrscr();

i=&a[1];

j=&a[4];

printf("\nvalue of i=%u",i);

printf("\nvalue of j=%u",j);

printf("\n%d %d",j-i,*j-*i);

getch();

}

Out put3 30


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4. comparison of two pointer variables.

pointer variables can be compared if both the pointer

variables point to the objects of the same data type.

comparisions can be useful when both pointer variables

point to elements of the same array.

void main()

{int a[]={10,20,30,40,50,60};

int *x,*y;

clrscr();

x=&a[4];

y=&a[5];if(x


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The following operations should not be applied on thepointers.

1. addition of two pointers.

2. multiplication of a pointer with a constant3. division of a pointer with a constant.

int x=10,y=20;int *i,*j;

i=&x;

j=&y;

printf(%d,i+j);

A d i t


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Arrays and pointers

Print the elements of the array using

subscript

void main(){

int arr[]={10,20,30,40,50};

int i;

for(i=0;i


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a g a ay a a g We can pass array elements as arguments to the called function in two ways

1. pass individual array element at a time.

2. pass the entire array at a time

1. passing individual array elements.

we can pass individual array elements to the called functions by either call by

value or call by reference.

Call by value

void main(){

int i;

int arr[]={10,20,30,40,50};

for(i=0;i


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. pass t e e t e a ay at a t e

Fixed length array- the size of the array is known when the

program is written. int arr[10];

Variable length array- the size of the array is known when theprogram is run. int arr[n];

If u want to pass the fixed length array as argument to the called

function, simply pass the array name to called function.void display(int x[]);

void main()

{

int arr[5]={10,20,30,40,50};

clrscr();display(arr);

getch();

}//main

void display(int x[])

{

int i;

for(i=0;i


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In variable length array we have to pass array name as well as

size of the array to the called function.void display(int arr[],int size);

void main()

{

int a[10];

int n,i;

clrscr();printf("\n enter the size of the array");

scanf("%d",&n);

for(i=0;i


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/* Demo: 2-D array is an array of arrays */

main( )

{

int s[4][2] = {

{ 1234, 56 },

{ 1212, 33 },

{ 1434, 80 },

{ 1312, 78 }

} ;

int i ;

for ( i = 0 ; i


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main( )

{

int s[4][2] = {

{ 1234, 56 },

{ 1212, 33 },{ 1434, 80 },

{ 1312, 78 }

} ;

int i, j ;

for ( i = 0 ; i


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Assign pointer to an 2-d array

void main( )

{

int s[4][2] = {

{ 1,10 },

{ 2, 20 },

{ 3, 30 },

{ 4, 40 }

} ;int ( *p )[2] ;

int i, j, *pint ;

for ( i = 0 ; i


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Array of pointers


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Array of pointers

void main( )

{

int *arr[4] ; /* array of integer pointers */int i = 31, j = 5, k = 19, l = 71, m ;

arr[0] = &i ;

arr[1] = &j ;

arr[2] = &k ;

arr[3] = &l ;

for ( m = 0 ; m


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int a[10];- it is an array of 10 integers

int *a[10];- it is an array of 10 integer

pointers

int (*a)[10];- it is a pointer to an array of 10

integers.


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Pointer as return type of a function

Called function returns pointer to the calling

function.

Example

void main()

{

int a,b;

Storage classes in c


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The storage class determines the part of member storage is allocated for anobject and how long the storage allocation continues to exit.

A scope specifies the part of the program which a variable name is visible,

that is the accessibility of the variable by its name. Storage class tells us:

1) Where the variable is stored.

2) Initial value of the variable.

3) Scope of the variable. Scope specifies the part of the program which a

variable is accessed.4) Life of the variable. How long variable exist in the program.

There are four types of storage classes:

1) Automatic storage class

2) Register storage class

3) Static storage class 4) External storage class


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2. Register storage class


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1. Automatic variables are allocated storage in the main memory of thecomputer; however, for most computers, accessing data in memory isconsiderably slower than processing directly in the CPU.

2. Registers are memory located within the CPU itself where data can be

stored and accessed quickly. Normally, the compiler determines whatdata is to be stored in the registers of the CPU at what times.

3. Thus, register variables provide a certain control over efficiency ofprogram execution.

4. Variables which are used repeatedly or whose access times are critical

may be declared to be of storage class register.5. Variables can be declared with keyword register as register int x;

6. Storage- variable stored in cpu registers rather than memory.

7. Default initial value- garbage value.

8. Scope- local to the block in which they are declared, including any

blocks nested within that block. For this reasons automatic variable arealso called local variable.

9. Life within the block in which the variable is defined.

3.Static storage class


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1. Variables must be declared with the key word static. static int x;

2. Storage- variable stored in computer memory.

3. Default initial value- zero.

4. Scope- local to the block in which they are declared.5. Lifevalue of the variable persists between the different function calls.

6. Static automatic variables continue to exist even after the block in whichthey are defined terminates. Thus, the value of a static variable in afunction is retained between repeated function calls to the same function.

7. In the case of recursive function calls we use static storage class.

8. Static variables may be initialized in their declarations; however, theinitializes must be constant expressions, and initialization is done onlyonce at compile time when memory is allocated for the static variable.

9. Static and auto variables are differ in their life and initial value.

Difference between static and auto


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Difference between static and auto

void main()

{

add();

add();

add();

getch();

}//mainadd()

{

auto int i=1;

printf(%d,i);

i++;}//add

void main()

{

add();

add();

add();

getch();

}//mainadd()

{

static int i=1;

printf(%d,i);

i++;}//add

Out put 1 1 1Out put 1 2 3

void main(){

static int i;

printf(%d,i);

}

Out put 0

4 External storage class


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4. External storage class1. All variables we have seen so far have had limited scope

(the block in which they are declared) and limited lifetimes

(as for automatic variables).2. These variables are declared with keyword extern as

extern int x; ( extern keyword may be omitted).

3. Storage- Memory.

4. Default initial value- zero.

5. Scope- as long as the programs execution.

6. Life- doesnt come to an end.

7. External variables are declared outside the all the functions.So that they are available to all the functions in a program.


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int i;void main()

{

printf(%d,i);->0add();--------1

add();------2

sub();------1

sub();----0

}//main()

add()

{

i++;

printf(i=%di);

}//add()

Sub(){

i--;

printf(i=%d,i);

}//sub()

extern int x=100;

void main()

{

int x=200;

printf(x=%d,x);

display();

}//

display(){

print(%d,x);

}

Note- local variable has highest

preference than global variable

so that local variable value gets

printed.


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int x=20;void main()

{

extern int y;

printf(%d %d,x,y);}

int y=20;

- If any variable declared out side of

the main is treated as extern variable/

global variable.

-If any variable declared as global

variable inside of the main that must

be declared with key word extern

and defined outside of the main.


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Initialization of strings


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Initialization of strings

char name[10]= hyderabad;or

char name[10]= {h,y,d,e,r,a,b,a,d,\0};

When character array is initialized we must explicitly specify

the null character. Character array initialized without specifying the size also.

char name[]=hyderabad;

Compiler automatically determines the size of this array based

on the no of elements initialized.

Reading string from terminal(keyboard)


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Reading string from terminal(keyboard)

scanf() can be used to read a string with format

specifier %s.char name[10];

Scanf(%s,name);

Scanf() function assigns the characters typed atkeyboard to array until the enter key is pressed.

once enter key is pressed, scanf() places a \0 character

at the end of an array.

Noteproblem with the scanf() function is that it terminates

input on the first white space it finds. So a string with multiple

words are not accepted by the string.

ex- hyderabad snist would not be accepted.

To read the multiple words of a string use another

f i


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function gets().

void main()

{

char name[30];

printf(enter the string);

gets(name);}

Writing\ display strings on to a screen


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Writing\ display strings on to a screen

We can use printf() function to display string on

to a screen with %s format specifier.

Printf(%s,name);

in this case also printf() function cannot print the

multiple words.

like hyderabad snist

To overcome this problem use puts() to display multipl

words.

unlike printf() function, puts() places the cursor to the

next line. \n is not necessar .


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Use puts and gets functions

void main()

{

char name[30];

puts(enter the string);

gets(name);

puts(name);}


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/* Program to demonstrate printing of a string */

void main( )

{

char name[ ] = "Klinsman" ;

int i = 0 ;

while ( i


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void main( ){


int i = 0 ;while ( name[i] != `\0' )

{

printf ( "%c", name[i] ) ;i++ ;

}

}

With the help of null character


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void main( ){


char *ptr ;ptr = name ; /* store base address of string */

while ( *ptr != `\0' )

{

printf ( "%c", *ptr ) ;

ptr++ ;

}

With the help of pointers to print string


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c progrmming(unit-iii)

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