structures and files

7/26/2019 Structures and Files

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TWO DIMENSIONAL DYNAMIC ARRAY

Creating a dynamic 2D array using Dynamic Memory Allocation and

accessing te elements using !ointers"#$itout using %&% and %'() and use te

dynamic 2D array to *ind te trans!ose o* a matri+"#include

#include

int main(void)

{ int row,col,i,j;

int **a;

clrscr(); printf("nter row and column!");

scanf("dd",row,col);

a$(int **)calloc(row,si%eof(int)); for(i$&;i


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1etch();

return &;

Write a C !rogram to multi!ly t$o matrices using t$o dimensional dynamic

arrays"You must cec, te correctness o* multi!lication rules $ile in!utting

te si-e o* te matrices to .e multi!lied and also you must not use any o*/&/and /'0 sym.ols in your $ole !rogram code"#include

#include

int main(void)

{ int r2,r3,c2,c3,i,j,4;

int **a2;

int **a3; int **am;

clrscr(); printf("nter the si%e of 2st matri0");

scanf("dd",r2,c2); printf("nter the si%e of 3nd matri0");

scanf("dd",r3,c3);

if(c25$r3) {

printf("6ron1 input555");

else

{

a2$(int **)calloc(r2,si%eof(int)); for(i$&;i


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printf("opulate the 3nd matri0,+n");

for(i$&;i


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#include

#include

#includestruct student

{

int roll;char name-8&;

float mar4s;

;int main(void)

{

struct student s;

sstem("clear");printf("nter 9oll!");

scanf("d",(s.roll));

printf("nter :ame!");

scanf("s",(s.name));printf("nter ar4s!");

scanf("f",(s.mar4s));printf("9oll$dn:ame$snar4s$3.3fn",s.roll,s.name,s.mar4s);

return &;

Creating a structure and accessing te structure elements using % ( Arro$

o!erator"#include

#include#include

struct student

{int roll;

char name-8&;

float mar4s;;

int main(void)

{

struct student s;

struct student *ptr;

ptr$s;sstem("clear");

printf("nter 9oll!");

scanf("d",(ptr+>roll));

printf("nter :ame!");scanf("s",(ptr+>name));

printf("nter ar4s!");

scanf("f",(ptr+>mar4s));


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printf("9oll$dn:ame$snar4s$3.3fn",ptr+>roll,ptr+>name,ptr+>mar4s);

return &;

Creating a structure and accessing te structure elements using

!ointer#$itout using % ( arro$ o!erator)"

#include

#include#include

struct student

{int roll;

char name-8&;

float mar4s;

;int main(void)

{

struct student s;struct student *ptr;

ptr$s;

sstem("clear");printf("nter 9oll!");

scanf("d",((*ptr).roll));

printf("nter :ame!");

scanf("s",((*ptr).name));printf("nter ar4s!");

scanf("f",((*ptr).mar4s));

printf("9oll$dn:ame$snar4s$3.3fn",(*ptr).roll,(*ptr).name,(*ptr).mar4s);return &;

Creating a dynamic structure using dynamic memory allocation and accessing

te structure elements using % ( arro$ o!erator"

#include

#include#include

struct student{

int roll;char name-8&;

float mar4s;

;int main(void)

{


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struct student *ptr;

ptr$(struct student *)malloc(si%eof(struct student));sstem("clear");


scanf("d",(ptr+>roll));printf("nter :ame!");

scanf("s",(ptr+>name));

printf("nter ar4s!");scanf("f",(ptr+>mar4s));

printf("9oll$dn:ame$snar4s$3.3fn",ptr+>roll,ptr+>name,ptr+>mar4s);

return &;

Creating a dynamic structure using dynamic memory allocation and accessing

te structure elements using !ointer#$itout using % ( arro$ o!erator)"

#include

#include

#include

struct student{

int roll;

char name-8&;float mar4s;

;

int main(void){

struct student *ptr;ptr$(struct student *)malloc(si%eof(struct student));

sstem("clear");


scanf("d",((*ptr).roll));printf("nter :ame!");

scanf("s",((*ptr).name));

printf("nter ar4s!");scanf("f",((*ptr).mar4s));

printf("9oll$dn:ame$snar4s$3.3fn",(*ptr).roll,(*ptr).name,(*ptr).mar4s);

return &;

Creating te array o* structures and accessing te structure array elements

using %"( Dot o!erator"#include

#include


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#include

struct student

{int roll;

char name-8&;

float mar4s;;

int main(void)

{int i,n;

struct student s-8&;

sstem("clear");

printf("nter the num7er of students!");scanf("d",n);

for(i$&;i


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printf("nter the num7er of students!");

scanf("d",n);

for(i$&;iroll));printf("nter :ame d!",i'2);

scanf("s",((s'i)+>name));

printf("nter ar4s d!",i'2);scanf("f",((s'i)+>mar4s));

for(i$&;iroll,(s'i)+>name,(s'i)+

>mar4s);

return &;

Creating te array o* structures and accessing te structure array elements

using !ointer #$itout using % ( Arro$ o!erator)"

#include

#include

#include

struct student{

int roll;


;

int main(void){

int i,n;

struct student s-8&;

sstem("clear");printf("nter the num7er of students!");

scanf("d",n);

for(i$&;i


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for(i$&;i


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Creating a dynamic array o* structures using dynamic memory allocation and

accessing te structure array elements using % ( Arro$ o!erator"

#include#include

#include

struct student{

int roll;


;

int main(void){

int i,n;

struct student *s;

sstem("clear");printf("nter the num7er of students!");

scanf("d",n);

s$(struct student *)malloc(n*si%eof(struct student));for(i$&;iroll));

printf("nter :ame d!",i'2);

scanf("s",((s'i)+>name));

printf("nter ar4s d!",i'2);scanf("f",((s'i)+>mar4s));

for(i$&;iroll,(s'i)+>name,(s'i)+>mar4s);

return &;

Creating a dynamic array o* structures and accessing te structure array

elements using !ointer #$itout using %

( Arro$ o!erator)"#include

#include#include

tpedef struct student

{int roll;

char name-8&;


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float mar4s;

1oru;

int main(void)

{

int i,n;1oru *s;

sstem("clear");

printf("nter the num7er of students!");scanf("d",n);

s$(1oru *)malloc(n*si%eof(1oru));

for(i$&;i


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printf("=ile Bpened uccessfulln");

fclose(fp);

return &;

5rogram to read a te+t *ile 7 dis!laying te content o* te *ile68#include

#include

#include#include

int is=ile0ist(const char *file:ame)

{ =? *fp;

if(fp$fopen(file:ame,"r"))

{

return 2;

fclose(fp);

else {

return &;

;

int main(void)

{

char file-8&; =? *fp;

int count; char ch; printf("nter file name!");

scanf("s",file);

if(is=ile0ist(file)) {

if(fp$fopen(file,"r"))

{ for(count$&;((ch$1etc(fp))5$B=)(5feof(fp));count'')

{

printf("c",ch);

printf("nd characters read",count);

fclose(fp);

else

{

fputs("rror Bpenin1 =ile555",stderr); e0it(2);


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else {

printf("=ile Coes not 0ist555");

return &;


#include

#include#include

#define DEFG 2&&


{

=? *fp; if(fp$fopen(file:ame,"r"))

{ return 2;

fclose(fp);

else

{

return &;

;

int main(void){ char file-8&;

=? *fp;

int count; char *str;

printf("nter file name!");

scanf("s",file); if(is=ile0ist(file))

{

if(fp$fopen(file,"r"))

{ str$(char *)calloc(DEFG,si%eof(char));

for(count$&;5feof(fp);count'')

{ fscanf(fp,"s",str);

printf("sc",str,1etc(fp));

fclose(fp);


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else

{ fputs("rror Bpenin1 =ile555",stderr);

e0it(2);

else

{ printf("=ile Coes not 0ist555");

return &;


#include

#include#include

#define DEFG 2&&int is=ile0ist(const char *file:ame)

{

=? *fp; if(fp$fopen(file:ame,"r"))

{

return 2;

fclose(fp);

else { return &;

;int main(void)

{

char file-8&; =? *fp;

int count;

char *str;

printf("nter file name!"); scanf("s",file);

if(is=ile0ist(file))

{ if(fp$fopen(file,"r"))

{

str$(char *)calloc(DEFG,si%eof(char)); for(count$&;fread(str,si%eof(str),2,fp)$$25feof(fp);count'')


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{

printf("s",str);

fclose(fp);

else {

fputs("rror Bpenin1 =ile555",stderr);

e0it(2);

else

{ printf("=ile Coes not 0ist555");

return &;

5rogram to $rite te contents o* a dynamic array o* structure into a *ile" I*

te *ile already e+ist a!!end te structure array contents6 create a ne$ *ile

and sa9e te contents oter$ise"#include

#include#include

#include

#define DEFG 2&&

tpedef struct student

{ int roll; char name-8&;

float mar4s;

stud;


{ =? *fp;

if(fp$fopen(file:ame,"r"))

{

return 2; fclose(fp);

else {

return &;

;


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int main(void)

{

char file-8&$"e!HHstudent.t0t"; =? *fp;

int count,i,n;

stud *s; printf("nter the no of students!");

scanf("d",n);

if(is=ile0ist(file)) {

if(fp$fopen(file,"a'"))

{

s$(stud *)calloc(n,si%eof(stud));

for(i$&;i


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scanf("s",((*s).name));

printf("nter mar4s d!",i'2);

scanf("f",((*s).mar4s));

for(i$&;i


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;

int main(void)

{ char file-8&$"e!HHstudent.t0t";

=? *fp;

int count,i,n; stud *s;

char str-8&;

printf("nter the no of students!"); scanf("d",n);

if(is=ile0ist(file))

{

if(fp$fopen(file,"a'")) {

s$(stud *)calloc(n,si%eof(stud));

for(i$&;i


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printf("nter name d!",i'2);

scanf("s",((*s).name));

printf("nter mar4s d!",i'2); scanf("f",((*s).mar4s));

for(i$&;i


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printf("nter name d!",i'2);

scanf("s",((*(s'i)).name));

printf("nter mar4s d!",i'2); scanf("f",((*(s'i)).mar4s));

printf("tudent Cata7ase!n+++++++++++++++++n"); for(i$&;i


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{

printf("tudent 9ecord#dn",i'2);

printf("9oll!dn",(*(r'i)).roll); printf(":ame!sn",(*(r'i)).name);

printf("ar4s!I.3fn",(*(r'i)).mar4s);

HHDnother wa to perform this

H*while(fread(r-count,si%eof(prana),2,fp)$$2)

{ count'';

*H

count$i;

printf("=ile records$dn",count); printf("nter the no of students!");

scanf("d",n);

s$(prana *)calloc(n,si%eof(prana));

if(s5$:@??) {

for(i$&;i


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int roll;

char name-8&;

float mar4s; prana;

int main(void)

{ int n,i,count$&;

clrscr();

=? *fp; prana *s;

s$(prana *)calloc(DEF/@C:/,si%eof(prana));

if((s$$:@??)JJ((fp$fopen("!student9ecord.7in","a'7"))$$:@??))

{ fputs("rror555",stderr);

e0it(2);

else {

rewind(fp); for(i$&;fread(s'i,si%eof(prana),2,fp)$$2;i'')

{

printf("tudent 9ecord#dn",i'2); printf("9oll!dn",(*(s'i)).roll);

printf(":ame!sn",(*(s'i)).name);

printf("ar4s!I.3fn",(*(s'i)).mar4s);

count$i;

printf("nd e0istin1 records retrievedn",count);

printf("nter the no of students!"); scanf("d",n);

if(n


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fclose(fp); 1etch();

return &;

Write a C !rogram to read %:oo,Title( ;string

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