SIRISHA SANAPATHI

26.6.20

c program dynamic memory management

DYNAMIC MEMORY MANAGEMENT

void main()

{

int *a,n,i;

printf("How many numbers do u want to enter ");

scanf("%d",&n);

a=(int*)malloc(n*sizeof(int));

printf("Enter numbers:");

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

scanf("%d",a+i);

printf("the entered numbers are\n");

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

printf("%d\n",*(a+i));

free(a);

}

OUTPUT

How many numbers do u want to enter 5

Enter numbers

956

324

8562

0159

Entered numbers are

956

324

8562

159

c program using arrays

USING ARRAYS:

void main()

{

int a[100],n,i;

printf("How many numbers do u want to enter:");

scanf("%d",&n);

printf("Enter numbers:");

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

scanf("%d",&a[i]);

printf("The entered numbers are\n");

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

printf("%d\n",a[i]);

}

OUTPUT:

How many numbers do u want to enter:4

Enter numbers:23

The entered numbers are

call by address example 2

CALL BY ADRESSS EXAMPLE 2

void changeMe(int*a)

{

*a=72;

}

void main()

{

int a=145;

printf("Before :%d\n",a);

changeMe(&a);

printf("After : %d",a);

}

OUTPUT

Before:145

After:72

call by address /reference example 1

CALL BY ADDRESS/REFERENCE EXAMPLE 1:

void swap(int*a,int *b)

{

int t;

t=*a;

*a=*b;

*b=t;

}

void main()

{

int a=10,b=20;

printf("Before swapping : %d,%d\n",a,b);

swap(&a,&b);

printf("After swapping : %d,%d\n",a,b);

}

OUTPUT

Before swapping 10,20

After swapping 20,10

call by value

CALL BY VALUE:

void swap(int a,int b)

{

int t;

t=a;

a=b;b=t;

}

void main()

{

int a=10,b=20;

printf("Before swapping : %d,%d\n",a,b);

swap(a,b);

printf("After swapping : %d,%d\n",a,b);

}

OUTPUT

Before swapping : 10,20

After swapping :10,20

Explanation :the a,b in main() and swap() functions are different....

So the changes made to a and b in the swap() function has no affect on a and b of main().

c program on arthmetic example 2

POINTER ARTHMETIC EXAMPLE 2

void main()

{

int a=10,b=20;

int*p=&a,*q=&b;

printf("%u,%u\n",p,q);

printf("%u\n",p+2);

printf("%u\n",p-2);

/* printf("%u\n",p*2); */

printf("%u\n",q-p);

/*printf("%u\n",p+q); illegal */

}

OUTPUT

6356724,6356720

6356732

6356716

4294967295

c program for pointer arthmetic

POINTER ARTHMETIC

void main()

{

int a=15;

char ch='x';

float f=9.7;

int*p=&a;

char*q=&ch;

float*r=&f;

printf("Before incremention:%d,%c,%f\n",a,ch,f);

a++;

ch++;

f++;

printf("after incremention:%d,%c,%f\n\n",a,ch,f);

printf("Before incremention:%d,%c,%f\n",p,q,r);

p++;

q++;

r++;

printf("after incremention:%d,%c,%f\n",p,q,r);

}

Before incrementation: 15,x,9.7

After incrementation: 16,y,10.7

Before incrementation:100,200,300

After incrementation: 102,201,304

C program for the necessary of different pointers

WHY DIFFERENT TYPES FOR POINTERS

void main()

{

int a=4873;

char ch='p';

float f=2173.964;

int *p;

p=&a;

printf("%u\n",*p);

p=&ch;

printf("u\n",*p);

p=&f;

printf("%u",*p);

}

OUTPUT

4873

garbage

c program for address of and value at operators example 2

ADDRESS OF AND VALUE AT OPERATORS EXAMPLE 2

void main()

{

int a=35;

int*p;

int**q;

p=&a;

q=&p;

printf("%u\n",p);

printf("%u\n",q);

printf("u\n",*q);

printf("u\n",*p);

/* printf ("%u\n",*a); illegal */

printf("%u\n",**q);

/* printf("%u\n",**p); illegal */

printf("%u",*&p);

}

OUTPUT

6356728

6356724

6356728

C program for size of a pointer

SIZE OF A POINTER

void main()

{

int a=10;

char ch='x';

float f=9.7;

int *p=&a;

char*q=&ch;

float*r=&f;

printf("%d,%d,%d\n",sizeof(a),sizeof(ch),sizeof(f));

printf("%d,%d,%d",sizeof(p),sizeof(q),sizeof(r));

}

OUTPUT

4,1,4

2,2,2

c program for address of and value at operators

ADDRESS OF AND VALUE AT OPERATORS

void main()

{

int a=35;

int *p;

p=&a;

printf("%u\n",a);

printf("%u\n",&a);

printf("%u\n",p);

printf("%u\n",&p);

printf("%u\n",*p);

}

OUTPUT

6356732

6353732

6357328

c program for to print an address

HOW TO PRINT AN ADDRESS

void main()

{

int a=10;

printf("%d\n",a);

printf("%u",&a);

}

OUTPUT

6356732

19.6.20

c global variable

GLOBAL VARIABLE:

int i=78;

void fun1()

{

printf("%d\n",i);

}

void fun2()

{

int i= 45;

printf("%d\n",i);

}

void main()

{

printf("%d\n",i);

fun1();

fun2();

}

OUTPUT:

c register storage class specifier

void main()

{

for(i=1;i<=5;i++)

printf("I LOVE INDIA.\n");

}

OUTPUT

I LOVE INDIA.

c static storage class

STATIC STORAGE CLASS :

void fun()

{

static int a=10;

printf("%d\n",a);

a++;

}

void main()

{

fun();

}

OUTPUT:

c auto storage class

AUTO STORAGE CLASS

void fun()

{

int a=10;

printf("%d\n",a);

a++;

}

void main()

{

fun();

}

OUTPUT

c macro: where we can access a variable

WHERE WE CAN ACCESS A VARIABLE...

void main()

{

int a=10;

printf("%d\n",a);

{

int b=20;

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

}

printf("%d,%d",a,b); /*error: b not accesible */

}

EXPALNATION:

A variable defined in a block can be accessed in that block and all its inner blocks (i.r., a variable defined in a block cannot be accessed in its outer block).It is called as the scope of a variable .

c macro :where to define a variable

WHERE TO DEFINE A VARIABLE

void main()

{

int a=10;

printf("%d\n",a);

{

int b=20;

printf("%d",b);

}

OUTPUT:

c program enclosing the variable in the macro expansion

IMPORTANCE OF ENCLOSING THE VARIABLES IN THE MACRO EXPANSION WITHIN PARENTHESIS

#include<math.h>

#define MAC(x,y)sqrt(x*x+y*y)

float fun(int x,int y)

{

return sqrt(x*x+y*y);

}

void main()

{

int a=3,b=4;

float p,q,r,s;

p=fun(a,b);

q=fun(a+1,b+1);

r=MAC(a,b);

s=MAC(a+1,b+1);

printf("Using functions:%f,%f\n",p,q);

printf("Using macros:%f,%f",r,s);

}

OUTPUT

Using functions: 5.0000000,6.403124

Using macros 5.0000000,4.000000

c program on name less blocks

PROGRAM ON NAMELESS BLOCKS

void main()

{

int a=10;

printf("%d\n",a);

{

printf("Stella Maris school -Marripalem");

}

OUTPUT

Stella Maris School-Marripalem

c program on macros with arguments

PROGRAM ON MACROS WITH ARGUMENTS

#define PI 3.142857

#define AREA(x)PI*x*x

void main()

{

float r,a;

printf("Enter radius of a circle");

scanf("%f",&r);

a=AREA(r);

printf("AREA of the circle=%f",a);

}

OUTPUT

Enter radius of a circle 45

AREA of the circle6364.285645

program on macros with arguments

PROGRAM ON MACROS WITH ARGUMENTS

#define SUM(a,b) a+b

void main()

{

int a,b;

printf("Enter two numbers");

scanf("%d%d",&a,&b);

printf("Sum=%d",SUM(a,b));

}

OUTPUT:

Enter two numbers:30 20

Sum=50

program on macros example 3

PROGRAM FOR MACROS EXAMPLE 3

#define PI 3.142857

void main()

{

float r,a;

printf("Enter radius of a circle:");

scanf("%f",&r);

a=PI*r*r;

printf("Area of circle:%f",a);

}

OUTPUT:

Enter radius of circle: 3

Area of circle: 285713

program on macros example 2

PROGRAM FOR MACROS 2

#define TRUE 1

void main()

{

while(TRUE)

{

printf("This loop runs infinite times\n");

}

OUTPUT

This loop runs infinite times

This loop runs infinite times.....................

program on macros example 1

PROGRAM FOR MACROS EXAMPLE 1

#define NULL 0

void main()

{

char st[20];

int i;

puts("Enter a string:");

gets(st);

for(i=0;st[i]!=NULL;i++);

printf("length=%d",i);

}

OUTPUT:

Enter a string:

Sirisha

Length=7

9.4.20

string sorting

STRING SORTING

#include<stdio.h>

#include<strings.h>

int main()

{

char st[10][30],t[30];

int n,i,j,flag;

printf("How many strings do u want to enter :");

scanf("%d",&n);

printf("Enter strings:");

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

{

fflush(stdin);

gets(st[i]);

}

for(i=0;i<n-1;i++)

{

flag=1;

for(j=0;j<n-1-i;j++)

{

if(strcmp(st[j],st[j+1])>0)

{

strcpy(t,st[j]);

strcpy(st[j],st[j+1]);

strcpy(st[j+1],t);

flag=0;

}

if(flag==1)

break;

}

printf("In alphabetical order\n");

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

printf("%s\n",st[i]);

return 0;

}

OUTPUT

How many strings do u want to enter 4

Sirisha

Dali

Deepthi

Rama

In alphabetical order

Dali

Deepthi

Rama

Sirisha

finding the string which occurs first in alphabetical order without modifying the array

FINDING THE STRING WHICH OCCURS FIRST IN ALPHABTICAL ORDER WITHOUT MODIFYING THE ARRAY

#include <stdio.h>

void main()

{

char st[10][30],t[30];

int n,i;

printf("how many strings do u want to enter :");

scanf("%d",&n);

printf("Enter strings:");

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

{

fflush(stdin);

gets(st[i]);

}

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

if(i==0||strcmp(t,st[i]>0))2

strcpy(t,st[i]);

printf("The string which occurs first in alphabetical order is %s",t);

}

OUPUT

How many strings do u want to enter :1

Enter strings: abcde

The string which occurs first in alphabetical order is abcde

finding the longest string

FINDING THE LONGEST STRING

#include <stdio.h>

void main()

{

char st[10][30],t[30];

int n,i,l,max=0;

printf("How many strings do u want ot enter:");

scanf("%d",&n);

printf("enter strings:");

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

{

fflush(stdin);

gets(st[i]);

l=strlen(st[i]);

if(l>max)

{

max=1;

strcpy(t,st[i]);

}

printf("Longest string is : %s",t);

}

OUTPUT

How many strings do u want to enter 2

Enter strings: sirisha

Sanapathi

Longest string sanapathi

reading and printing a set of strings

READING /PRINTING A SET OF STRINGS

#include <stdio.h>

void main()

{

char st[10][30];

int n,i;

printf("how many strings do u want to enter:");

scanf("%d",&n);

printf("Enter strings:");

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

{

fflush(stdin);

gets(st[i]);

}

printf("The entered strings are\n");

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

printf("%s\n",st[i]);

}

OUTPUT

How mant strings do u want to enter : 5

Enter strings:Dwarakanagar

MVP

Gajuwaka

Scindia

NAD

The entered strings are : Dwarakanagar

MVP

Gajuwaka

Scindia

NAD

transpose matrix

TRANSPOSE MATRIX

#include <stdio.h>

void main()

{

int m[5][5],t[5][5],i,j,r,c;

printf("How many rows and cols");

scanf("%d%d",&r,&c);

printf("enter the matrix:");

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

for(j=0;j<c;j++)

scanf("%d",&m[i][j]);

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

for(j=0;j<c;j++)

t[j][i]=m[i][j];

printf("original matrix:\n");

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

{

for(j=0;j<c;j++)

printf("%5d",m[i][j]);

printf("\n");

}

printf("\n its transpose:\n");

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

{

for(j=0;j<r;j++)

printf("%5d",t[i][j]);

printf("\n");

}

OUTPUT

How many rows and cols 2

Enter the matrix: 1

Orginal matrix:

1 2

2 4

Its transpose

1 3

2 4

product of two matrices

PRODUCT OF TWO MATRICES

#include <stdio.h>

void main()

{

int m1[5][5],m2[5][5],m3[5][5]={0},r1,r2,c1,c2,i,j,k;

printf("how many rows and cols for matrix 1");

scanf("%d%d",&r1,&c1);

printf("how many rows and cols for matrix 2");

scanf("%d%d",&r2,&c2);

if(c1!=r2)

{

printf("Multiplication rule violated -cannot be multiplied");

exit(0);

}

printf("Enter elements into matrix 1:");

for(i=0;i<r1;i++)

for(j=0;j<c1;j++)

scanf("%d",&m1[i][j]);

printf("Enter elements into matrix 2:");

for(i=0;i<r2;i++)

for(j=0;j<c2;j++)

scanf("%d",&m2[i][j]);

for(i=0;i<r1;i++)

{

for(j=0;j<c2;j++)

{

for(k=0;k<c1;k++)

m3[i][j]=m3[i][j]+m1[i][j]*m2[i][j];

}

printf("Product of two matrices:\n");

for(i=0;i<r1;i++)

{

for(j=0;j<c2;j++)

printf("%5d",m3[i][j]);

printf("\n");

}

OUTPUT

How many rows and cols for matrix 1 2

How may rows and cols for matrix 2 2

Enter element into matrix 1:1

Enter element into matrix 2:1

Product of two matrices:

2 8

18 32

sum of two matrices

SUM OF TWO MATRICES

#include <stdio.h>

void main()

{

int m1[5][5],m2[5][5],m3[5][5],r,c,i,j;

printf("how many rows and cols ");

scanf("%d%d",&r,&c);

printf("Enter elements into matrix 1:");

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

for(j=0;j<c;j++)

scanf("%d",&m1[i][j]);

printf("Enter elements into matrix 2:");

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

for(j=0;j<c;j++)

scanf("%d",&m2[i][j]);

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

for(j=0;j<c;j++)

m3[i][j]=m1[i][j]+m2[i][j];

printf("sum of two matrices:\n");

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

{

for(j=0;j<c;j++)

printf("%3d",m3[i][j]);

printf("\n");

}

OUTPUT

How many rows and cols 2

Enter elements into matrix 1:1

Enter elements into matrix 2:1

Sum of matrices:

2 4

6 8