The program is given below-

/*Insertion ,Deletion, Display and Traversal in Binary Search Tree*/
# include
# include

struct node
{
int info;
struct node *lchild;
struct node *rchild;
}*root;

main()
{
int choice,num;
root=NULL;
while (1)
{
printf("\n");
printf( "1.Insert\ n");
printf("2.Delete\n");
p rintf ("3.Inorder Traversal\n");
printf("4.Preo rder Traversal\n");
printf("5.Post order Traversal\n");
printf("6.Disp lay\n ");
printf("7.Quit\n");
prin tf("E nter your choice : ");
scanf("%d",&choice);

s witch (choice)
{
case 1:
printf("Enter the number to be inserted : ");
scanf("%d",&num);
insert (num) ;
break;
case 2:
printf("Enter the number to be deleted : ");
scanf("%d",&num);
del(nu m);
break;
case 3:
inorder(root);
break;
ca se 4:
preorder(root);
break;
c ase 5:
postorder(root);
break;
case 6:
display(root,1);
break;
case 7:
exit();
default:
printf( "Wron g choice\n");
}/*End of switch */
}/*End of while */
}/*End of main()*/

find(int item,struct node **par,struct node **loc)
{
struct node *ptr,*ptrsave;

if(root==NUL L) /*tree empty*/
{
*loc=NULL;
*par=N ULL;
return;
}
if(item==roo t->info) /*item is at root*/
{
*loc=root;
*par=NU LL;
return;
}
/*Initialize ptr and ptrsave*/
if(iteminfo)
ptr=r oot-> lchild;
else
ptr=root->rchil d;
p trsave=root;

while(ptr!=NUL L)
{
if(item==ptr->info)
{ *loc=ptr;
*par=ptrsave;
retu rn;
}
ptrsave=ptr;
if(itemi nfo)
ptr= ptr->lchild;
else
ptr=ptr->r child ;
}/*End of while */
*loc=NULL; /*item not found*/
*par=ptrsave;
}/*End of find()*/

insert(int item)
{ struct node *tmp,*parent,*location;
find( item, &parent,&location);
if(locati on!=N ULL)
{
printf("Item already present");
return;
}

tmp= (stru ct node *)malloc(sizeof(struct node));
tmp->info=item;
tmp- >lchi ld=NULL;
tmp->rchild=NULL;

if(p arent==NULL)
root=tmp;
else
if(i teminfo)
parent->lchild=tmp;
else
parent->rchild=tmp;
}/ *End of insert()*/

Answered by Yash , an ibibo Master, at 9:33 AM on June 27, 2008

The program is given below-

/*Insertion ,Deletion, Display and Traversal in Binary Search Tree*/
# include
# include

struct node
{
int info;
struct node *lchild;
struct node *rchild;
}*root;

main()
{
int choice,num;
root=NULL;
while (1)
{
printf("\n");
printf( "1.Insert\ n");
printf("2.Delete\n");
p rintf ("3.Inorder Traversal\n");
printf("4.Preo rder Traversal\n");
printf("5.Post order Traversal\n");
printf("6.Disp lay\n ");
printf("7.Quit\n");
prin tf("E nter your choice : ");
scanf("%d",&choice);

s witch (choice)
{
case 1:
printf("Enter the number to be inserted : ");
scanf("%d",&num);
insert (num) ;
break;
case 2:
printf("Enter the number to be deleted : ");
scanf("%d",&num);
del(nu m);
break;
case 3:
inorder(root);
break;
ca se 4:
preorder(root);
break;
c ase 5:
postorder(root);
break;
case 6:
display(root,1);
break;
case 7:
exit();
default:
printf( "Wron g choice\n");
}/*End of switch */
}/*End of while */
}/*End of main()*/

find(int item,struct node **par,struct node **loc)
{
struct node *ptr,*ptrsave;

if(root==NUL L) /*tree empty*/
{
*loc=NULL;
*par=N ULL;
return;
}
if(item==roo t->info) /*item is at root*/
{
*loc=root;
*par=NU LL;
return;
}
/*Initialize ptr and ptrsave*/
if(iteminfo)
ptr=r oot-> lchild;
else
ptr=root->rchil d;
p trsave=root;

while(ptr!=NUL L)
{
if(item==ptr->info)
{ *loc=ptr;
*par=ptrsave;
retu rn;
}
ptrsave=ptr;
if(itemi nfo)
ptr= ptr->lchild;
else
ptr=ptr->r child ;
}/*End of while */
*loc=NULL; /*item not found*/
*par=ptrsave;
}/*End of find()*/

insert(int item)
{ struct node *tmp,*parent,*location;
find( item, &parent,&location);
if(locati on!=N ULL)
{
printf("Item already present");
return;
}

tmp= (stru ct node *)malloc(sizeof(struct node));
tmp->info=item;
tmp- >lchi ld=NULL;
tmp->rchild=NULL;

if(p arent==NULL)
root=tmp;
else
if(i teminfo)
parent->lchild=tmp;
else
parent->rchild=tmp;
}/ *End of insert()*/

del(int item)
{
struct node *parent,*location;
if(root==N ULL)
{
printf("Tree empty");
return;
}

find(i tem,& parent,&location);
if(locatio n==NU LL)
{
printf("Item not present in tree");
return;
}

if(loca tion- >lchild==NULL && location->rchild==NULL)
case_ a(par ent,location);
if(location->l child !=NULL && location->rchild==NULL)
case_ b(par ent,location);
if(location->l child ==NULL && location->rchild!=NULL)
case_ b(par ent,location);
if(location->l child !=NULL && location->rchild!=NULL)
case_ c(par ent,location);
free(location) ;
}/ *End of del()*/

case_a(struct node *par,struct node *loc )
{
if(par==NULL) /*item to be deleted is root node*/
root=NULL;
else
if(l oc==p ar->lchild)
par->lchild=NULL;
els e
par->rchild=NULL;
}/*End of case_a()*/

case_b(struct node *par,struct node *loc)
{
struct node *child;

/*Initialize child*/
if(loc->lchild!=NULL) /*item to be deleted has lchild */
child=loc->lchild;
else /*item to be deleted has rchild */
child=loc->rchild;

if(p ar==N ULL ) /*Item to be deleted is root node*/
root

Answered by Raksha , an ibibo Master, at 9:23 AM on June 27, 2008

well, Here we give a linked list program in c with insertion, deletion, display and traversal.

The program is given below-

/*Insertion ,Deletion, Display and Traversal in Binary Search Tree*/
# include
# include

struct node
{
int info;
struct node *lchild;
struct node *rchild;
}*root;

main()
{
int choice,num;
root=NULL;
while (1)
{
printf("\n");
printf( "1.Insert\ n");
printf("2.Delete\n");
p rintf ("3.Inorder Traversal\n");
printf("4.Preo rder Traversal\n");
printf("5.Post order Traversal\n");
printf("6.Disp lay\n ");
printf("7.Quit\n");
prin tf("E nter your choice : ");
scanf("%d",&choice);

s witch (choice)
{
case 1:
printf("Enter the number to be inserted : ");
scanf("%d",&num);
insert (num) ;
break;
case 2:
printf("Enter the number to be deleted : ");
scanf("%d",&num);
del(nu m);
break;
case 3:
inorder(root);
break;
ca se 4:
preorder(root);
break;
c ase 5:
postorder(root);
break;
case 6:
display(root,1);
break;
case 7:
exit();
default:
printf( "Wron g choice\n");
}/*End of switch */
}/*End of while */
}/*End of main()*/

find(int item,struct node **par,struct node **loc)
{
struct node *ptr,*ptrsave;

if(root==NUL L) /*tree empty*/
{
*loc=NULL;
*par=N ULL;
return;
}
if(item==roo t->info) /*item is at root*/
{
*loc=root;
*par=NU LL;
return;
}
/*Initialize ptr and ptrsave*/
if(iteminfo)
ptr=r oot-> lchild;
else
ptr=root->rchil d;
p trsave=root;

while(ptr!=NUL L)
{
if(item==ptr->info)
{ *loc=ptr;
*par=ptrsave;
retu rn;
}
ptrsave=ptr;
if(itemi nfo)
ptr= ptr->lchild;
else
ptr=ptr->r child ;
}/*End of while */
*loc=NULL; /*item not found*/
*par=ptrsave;
}/*End of find()*/

insert(int item)
{ struct node *tmp,*parent,*location;
find( item, &parent,&location);
if(locati on!=N ULL)
{
printf("Item already present");
return;
}

tmp= (stru ct node *)malloc(sizeof(struct node));
tmp->info=item;
tmp- >lchi ld=NULL;
tmp->rchild=NULL;

if(p arent==NULL)
root=tmp;
else
if(i teminfo)
parent->lchild=tmp;
else
parent->rchild=tmp;
}/ *End of insert()*/

del(int item)
{
struct node *parent,*location;
if(root==N ULL)
{
printf("Tree empty");
return;
}

find(i tem,& parent,&location);
if(locatio n==NU LL)
{
printf("Item not present in tree");
return;
}

if(loca tion- >lchild==NULL && location->rchild==NULL)
case_ a(par ent,location);
if(location->l child !=NULL && location->rchild==NULL)
case_ b(par ent,location);
if(location->l child ==NULL && location->rchild!=NULL)
case_ b(par ent,location);
if(location->l child !=NULL && location->rchild!=NULL)
case_ c(par ent,location);
free(location) ;
}/ *End of del()*/

case_a(struct node *par,struct node *loc )
{
if(par==NULL) /*item to be deleted is root node*/
root=NULL;
else
if(l oc==p ar->lchild)
par->lchild=NULL;
els e
par->rchild=NULL;
}/*End of case_a()*/

case_b(struct node *par,struct node *loc)
{
struct node *child;

/*Initialize child*/
if(loc->lchild!=NULL) /*item to be deleted has lchild */
child=loc->lchild;
else /*item to be deleted has rchild */
child=loc->rchild;

if(p ar==N UL

Answered by Romi , an ibibo Master, at 6:39 PM on June 20, 2008

/*Insertion ,Deletion, Display and Traversal in Binary Search Tree*/
# include
# include

struct node
{
int info;
struct node *lchild;
struct node *rchild;
}*root;

main()
{
int choice,num;
root=NULL;
while (1)
{
printf("\n");
printf( "1.Insert\ n");
printf("2.Delete\n");
p rintf ("3.Inorder Traversal\n");
printf("4.Preo rder Traversal\n");
printf("5.Post order Traversal\n");
printf("6.Disp lay\n ");
printf("7.Quit\n");
prin tf("E nter your choice : ");
scanf("%d",&choice);

s witch (choice)
{
case 1:
printf("Enter the number to be inserted : ");
scanf("%d",&num);
insert (num) ;
break;
case 2:
printf("Enter the number to be deleted : ");
scanf("%d",&num);
del(nu m);
break;
case 3:
inorder(root);
break;
ca se 4:
preorder(root);
break;
c ase 5:
postorder(root);
break;
case 6:
display(root,1);
break;
case 7:
exit();
default:
printf( "Wron g choice\n");
}/*End of switch */
}/*End of while */
}/*End of main()*/

find(int item,struct node **par,struct node **loc)
{
struct node *ptr,*ptrsave;

if(root==NUL L) /*tree empty*/
{
*loc=NULL;
*par=N ULL;
return;
}
if(item==roo t->info) /*item is at root*/
{
*loc=root;
*par=NU LL;
return;
}
/*Initialize ptr and ptrsave*/
if(iteminfo)
ptr=r oot-> lchild;
else
ptr=root->rchil d;
p trsave=root;

while(ptr!=NUL L)
{
if(item==ptr->info)
{ *loc=ptr;
*par=ptrsave;
retu rn;
}
ptrsave=ptr;
if(itemi nfo)
ptr= ptr->lchild;
else
ptr=ptr->r child ;
}/*End of while */
*loc=NULL; /*item not found*/
*par=ptrsave;
}/*End of find()*/

insert(int item)
{ struct node *tmp,*parent,*location;
find( item, &parent,&location);
if(locati on!=N ULL)
{
printf("Item already present");
return;
}

tmp= (stru ct node *)malloc(sizeof(struct node));
tmp->info=item;
tmp- >lchi ld=NULL;
tmp->rchild=NULL;

if(p arent==NULL)
root=tmp;
else
if(i teminfo)
parent->lchild=tmp;
else
parent->rchild=tmp;
}/ *End of insert()*/

del(int item)
{
struct node *parent,*location;
if(root==N ULL)
{
printf("Tree empty");
return;
}

find(i tem,& parent,&location);
if(locatio n==NU LL)
{
printf("Item not present in tree");
return;
}

if(loca tion- >lchild==NULL && location->rchild==NULL)
case_ a(par ent,location);
if(location->l child !=NULL && location->rchild==NULL)
case_ b(par ent,location);
if(location->l child ==NULL && location->rchild!=NULL)
case_ b(par ent,location);
if(location->l child !=NULL && location->rchild!=NULL)
case_ c(par ent,location);
free(location) ;
}/ *End of del()*/

case_a(struct node *par,struct node *loc )
{
if(par==NULL) /*item to be deleted is root node*/
root=NULL;
else
if(l oc==p ar->lchild)
par->lchild=NULL;
els e
par->rchild=NULL;
}/*End of case_a()*/

case_b(struct node *par,struct node *loc)
{
struct node *child;

/*Initialize child*/
if(loc->lchild!=NULL) /*item to be deleted has lchild */
child=loc->lchild;
else /*item to be deleted has rchild */
child=loc->rchild;

if(p ar==N ULL ) /*Item to be deleted is root node*/
root

Answered by Sharad Singh , an ibibo Master, at 6:27 PM on June 05, 2008

The program is given below-

/*Insertion ,Deletion, Display and Traversal in Binary Search Tree*/
# include
# include

struct node
{
int info;
struct node *lchild;
struct node *rchild;
}*root;

main()
{
int choice,num;
root=NULL;
while (1)
{
printf("\n");
printf( "1.Insert\ n");
printf("2.Delete\n");
p rintf ("3.Inorder Traversal\n");
printf("4.Preo rder Traversal\n");
printf("5.Post order Traversal\n");
printf("6.Disp lay\n ");
printf("7.Quit\n");
prin tf("E nter your choice : ");
scanf("%d",&choice);

s witch (choice)
{
case 1:
printf("Enter the number to be inserted : ");
scanf("%d",&num);
insert (num) ;
break;
case 2:
printf("Enter the number to be deleted : ");
scanf("%d",&num);
del(nu m);
break;
case 3:
inorder(root);
break;
ca se 4:
preorder(root);
break;
c ase 5:
postorder(root);
break;
case 6:
display(root,1);
break;
case 7:
exit();
default:
printf( "Wron g choice\n");
}/*End of switch */
}/*End of while */
}/*End of main()*/

find(int item,struct node **par,struct node **loc)
{
struct node *ptr,*ptrsave;

if(root==NUL L) /*tree empty*/
{
*loc=NULL;
*par=N ULL;
return;
}
if(item==roo t->info) /*item is at root*/
{
*loc=root;
*par=NU LL;
return;
}
/*Initialize ptr and ptrsave*/
if(iteminfo)
ptr=r oot-> lchild;
else
ptr=root->rchil d;
p trsave=root;

while(ptr!=NUL L)
{
if(item==ptr->info)
{ *loc=ptr;
*par=ptrsave;
retu rn;
}
ptrsave=ptr;
if(itemi nfo)
ptr= ptr->lchild;
else
ptr=ptr->r child ;
}/*End of while */
*loc=NULL; /*item not found*/
*par=ptrsave;
}/*End of find()*/

insert(int item)
{ struct node *tmp,*parent,*location;
find( item, &parent,&location);
if(locati on!=N ULL)
{
printf("Item already present");
return;
}

tmp= (stru ct node *)malloc(sizeof(struct node));
tmp->info=item;
tmp- >lchi ld=NULL;
tmp->rchild=NULL;

if(p arent==NULL)
root=tmp;
else
if(i teminfo)
parent->lchild=tmp;
else
parent->rchild=tmp;
}/ *End of insert()*/

del(int item)
{
struct node *parent,*location;
if(root==N ULL)
{
printf("Tree empty");
return;
}

find(i tem,& parent,&location);
if(locatio n==NU LL)
{
printf("Item not present in tree");
return;
}

if(loca tion- >lchild==NULL && location->rchild==NULL)
case_ a(par ent,location);
if(location->l child !=NULL && location->rchild==NULL)
case_ b(par ent,location);
if(location->l child ==NULL && location->rchild!=NULL)
case_ b(par ent,location);
if(location->l child !=NULL && location->rchild!=NULL)
case_ c(par ent,location);
free(location) ;
}/ *End of del()*/

case_a(struct node *par,struct node *loc )
{
if(par==NULL) /*item to be deleted is root node*/
root=NULL;
else
if(l oc==p ar->lchild)
par->lchild=NULL;
els e
par->rchild=NULL;
}/*End of case_a()*/

case_b(struct node *par,struct node *loc)
{
struct node *child;

/*Initialize child*/
if(loc->lchild!=NULL) /*item to be deleted has lchild */
child=loc->lchild;
else /*item to be deleted has rchild */
child=loc->rchild;

if(p ar==N ULL ) /*Item to be deleted is root node*/
root

Answered by kishore , an ibibo Master, at 8:31 AM on June 03, 2008

The program is given below-

/*Insertion ,Deletion, Display and Traversal in Binary Search Tree*/
# include
# include

struct node
{
int info;
struct node *lchild;
struct node *rchild;
}*root;

main()
{
int choice,num;
root=NULL;
while(1)
{
printf("\n");
printf("1.Insert\ n");
printf("2.Delete\n");
printf ("3.Inorder Traversal\n");
printf("4.Preorder Traversal\n");
printf("5.Postorder Traversal\n");
printf("6.Display\n ");
printf("7.Quit\n");
printf("E nter your choice : ");
scanf("%d",&choice);

switch (choice)
{
case 1:
printf("Enter the number to be inserted : ");
scanf("%d",&num);
insert(num) ;
break;
case 2:
printf("Enter the number to be deleted : ");
scanf("%d",&num);
del(num);
break;
case 3:
inorder(root);
break;
case 4:
preorder(root);
break;
case 5:
postorder(root);
break;
case 6:
display(root,1);
break;
case 7:
exit();
default:
printf("Wron g choice\n");
}/*End of switch */
}/*End of while */
}/*End of main()*/

find(int item,struct node **par,struct node **loc)
{
struct node *ptr,*ptrsave;

if(root==NULL) /*tree empty*/
{
*loc=NULL;
*par=NULL;
return;
}
if(item==root->info) /*item is at root*/
{
*loc=root;
*par=NULL;
return;
}
/*Initialize ptr and ptrsave*/
if(iteminfo)
ptr=root-> lchild;
else
ptr=root->rchild;
p trsave=root;

while(ptr!=NULL)
{
if(item==ptr->info)
{ *loc=ptr;
*par=ptrsave;
return;
}
ptrsave=ptr;
if(iteminfo)
ptr= ptr->lchild;
else
ptr=ptr->rchild ;
}/*End of while */
*loc=NULL; /*item not found*/
*par=ptrsave;
}/*End of find()*/

insert(int item)
{ struct node *tmp,*parent,*location;
find(item, &parent,&location);
if(location!=N ULL)
{
printf("Item already present");
return;
}

tmp=(stru ct node *)malloc(sizeof(struct node));
tmp->info=item;
tmp->lchi ld=NULL;
tmp->rchild=NULL;

if(p arent==NULL)
root=tmp;
else
if(i teminfo)
parent->lchild=tmp;
else
parent->rchild=tmp;
}/*End of insert()*/

del(int item)
{
struct node *parent,*location;
if(root==NULL)
{
printf("Tree empty");
return;
}

find(item,& parent,&location);
if(location==NU LL)
{
printf("Item not present in tree");
return;
}

if(location- >lchild==NULL && location->rchild==NULL)
case_a(par ent,location);
if(location->lchild !=NULL && location->rchild==NULL)
case_b(par ent,location);
if(location->lchild ==NULL && location->rchild!=NULL)
case_b(par ent,location);
if(location->lchild !=NULL && location->rchild!=NULL)
case_c(par ent,location);
free(location);
}/ *End of del()*/

case_a(struct node *par,struct node *loc )
{
if(par==NULL) /*item to be deleted is root node*/
root=NULL;
else
if(loc==p ar->lchild)
par->lchild=NULL;
els e
par->rchild=NULL;
}/*End of case_a()*/

case_b(struct node *par,struct node *loc)
{
struct node *child;

/*Initialize child*/
if(loc->lchild!=NULL) /*item to be deleted has lchild */
child=loc->lchild;
else /*item to be deleted has rchild */
child=loc->rchild;

if(par==N ULL ) /*Item to be deleted is root node*/
root

Answered by Reeta K , an ibibo Master, at 6:34 PM on June 02, 2008

well, Here we give a linked list program in c with insertion, deletion, display and traversal.

The program is given below-

/*Insertion ,Deletion, Display and Traversal in Binary Search Tree*/
# include
# include

struct node
{
int info;
struct node *lchild;
struct node *rchild;
}*root;

main()
{
int choice,num;
root=NULL;
while (1)
{
printf("\n");
printf( "1.Insert\ n");
printf("2.Delete\n");
p rintf ("3.Inorder Traversal\n");
printf("4.Preo rder Traversal\n");
printf("5.Post order Traversal\n");
printf("6.Disp lay\n ");
printf("7.Quit\n");
prin tf("E nter your choice : ");
scanf("%d",&choice);

s witch (choice)
{
case 1:
printf("Enter the number to be inserted : ");
scanf("%d",&num);
insert (num) ;
break;
case 2:
printf("Enter the number to be deleted : ");
scanf("%d",&num);
del(nu m);
break;
case 3:
inorder(root);
break;
ca se 4:
preorder(root);
break;
c ase 5:
postorder(root);
break;
case 6:
display(root,1);
break;
case 7:
exit();
default:
printf( "Wron g choice\n");
}/*End of switch */
}/*End of while */
}/*End of main()*/

find(int item,struct node **par,struct node **loc)
{
struct node *ptr,*ptrsave;

if(root==NUL L) /*tree empty*/
{
*loc=NULL;
*par=N ULL;
return;
}
if(item==roo t->info) /*item is at root*/
{
*loc=root;
*par=NU LL;
return;
}
/*Initialize ptr and ptrsave*/
if(iteminfo)
ptr=r oot-> lchild;
else
ptr=root->rchil d;
p trsave=root;

while(ptr!=NUL L)
{
if(item==ptr->info)
{ *loc=ptr;
*par=ptrsave;
retu rn;
}
ptrsave=ptr;
if(itemi nfo)
ptr= ptr->lchild;
else
ptr=ptr->r child ;
}/*End of while */
*loc=NULL; /*item not found*/
*par=ptrsave;
}/*End of find()*/

insert(int item)
{ struct node *tmp,*parent,*location;
find( item, &parent,&location);
if(locati on!=N ULL)
{
printf("Item already present");
return;
}

tmp= (stru ct node *)malloc(sizeof(struct node));
tmp->info=item;
tmp- >lchi ld=NULL;
tmp->rchild=NULL;

if(p arent==NULL)
root=tmp;
else
if(i teminfo)
parent->lchild=tmp;
else
parent->rchild=tmp;
}/ *End of insert()*/

del(int item)
{
struct node *parent,*location;
if(root==N ULL)
{
printf("Tree empty");
return;
}

find(i tem,& parent,&location);
if(locatio n==NU LL)
{
printf("Item not present in tree");
return;
}

if(loca tion- >lchild==NULL && location->rchild==NULL)
case_ a(par ent,location);
if(location->l child !=NULL && location->rchild==NULL)
case_ b(par ent,location);
if(location->l child ==NULL && location->rchild!=NULL)
case_ b(par ent,location);
if(location->l child !=NULL && location->rchild!=NULL)
case_ c(par ent,location);
free(location) ;
}/ *End of del()*/

case_a(struct node *par,struct node *loc )
{
if(par==NULL) /*item to be deleted is root node*/
root=NULL;
else
if(l oc==p ar->lchild)
par->lchild=NULL;
els e
par->rchild=NULL;
}/*End of case_a()*/

case_b(struct node *par,struct node *loc)
{
struct node *child;

/*Initialize child*/
if(loc->lchild!=NULL) /*item to be deleted has lchild */
child=loc->lchild;
else /*item to be deleted has rchild */
child=loc->rchild;

if(p ar==N ULL

Answered by Saurabh , an ibibo Master, at 9:31 AM on June 02, 2008

A linked list is a complex data structure, especially useful in systems or applications programming. A linked list is comprised of a series of nodes, each node containing a data element, and a pointer to the next node, eg,

-------- --------
| data | --->| data |
|--------| | |--------|
| pointer|---- | pointer| ---> NULL
-------- --------


A structure which contains a data element and a pointer to the next node is created by,

struct list {
int value;
struct list *next;
};

This defines a new data structure called list (actually the definition of a node), which contains two members. The first is an integer called value. The second is called next, which is a pointer to another list structure (or node). Suppose that we declare two structures to be of the same type as list, eg,

struct list n1, n2;

The next pointer of structure n1 may be set to point to the n2 structure by

/* assign address of first element in n2 to the pointer next of the n1 structure */
n1.next = &n2;

which creates a link between the two structures.

/* LLIST.C Program to illustrate linked lists */
#include <stdio.h>
struct list {
int value;
struct list *next;
};

main()
{
struc t list n1, n2, n3;
int i;

n1.value = 100;
n2.value = 200;
n3.value = 300;
n1.next = &n2;
n2.next = &n3;
i = n1.next->value;
printf("%d\n" , n2.next->value);
}

Not only this, but consider the following


n1.next = n2.next /* deletes n2 */
n2_3.next = n2.next; /* adds struct n2_3 */
n2.next = &n2_3;

In using linked list structures, it is common to assign the value of 0 to the last pointer in the list, to indicate that there are no more nodes in the list, eg,


n3.next = 0;


Traversing a linked list

/* Program to illustrate traversing a list */
#include <stdio.h>
struct list {
int value;
struct list *next;
};

main()
{
struc t list n1, n2, n3, n4;
struct list *list_pointer = &n1;

n1.value = 100;
n1.next = &n2;
n2.value = 200;
n2.next = &n3;
n3.value = 300;
n3.next = &n4;
n4.value = 400;
n4.next = 0;


while( list_pointer != 0 ) {
printf("%d\n", list_pointer->value);
list_po in ter = list_pointer->next;
}
}

T hi s program uses a pointer called list_pointer to cycle through the linked list.

For more details , please visit the source site :

http://gd.tuwien.ac.at/la nguag es/c/programming-bbrown/c_086. htm

Answered by Shobhit , an ibibo Master, at 8:15 PM on May 30, 2008

A linked list is a complex data structure, especially useful in systems or applications programming. A linked list is comprised of a series of nodes, each node containing a data element, and a pointer to the next node, eg,

-------- --------
| data | --->| data |
|--------| | |--------|
| pointer|---- | pointer| ---> NULL
-------- --------


A structure which contains a data element and a pointer to the next node is created by,

struct list {
int value;
struct list *next;
};

This defines a new data structure called list (actually the definition of a node), which contains two members. The first is an integer called value. The second is called next, which is a pointer to another list structure (or node). Suppose that we declare two structures to be of the same type as list, eg,

struct list n1, n2;

The next pointer of structure n1 may be set to point to the n2 structure by

/* assign address of first element in n2 to the pointer next of the n1 structure */
n1.next = &n2;

which creates a link between the two structures.

/* LLIST.C Program to illustrate linked lists */
#include <stdio.h>
struct list {
int value;
struct list *next;
};

main()
{
struc t list n1, n2, n3;
int i;

n1.value = 100;
n2.value = 200;
n3.value = 300;
n1.next = &n2;
n2.next = &n3;
i = n1.next->value;
printf("%d\n" , n2.next->value);
}

Not only this, but consider the following


n1.next = n2.next /* deletes n2 */
n2_3.next = n2.next; /* adds struct n2_3 */
n2.next = &n2_3;

In using linked list structures, it is common to assign the value of 0 to the last pointer in the list, to indicate that there are no more nodes in the list, eg,


n3.next = 0;


Traversing a linked list

/* Program to illustrate traversing a list */
#include <stdio.h>
struct list {
int value;
struct list *next;
};

main()
{
struc t list n1, n2, n3, n4;
struct list *list_pointer = &n1;

n1.value = 100;
n1.next = &n2;
n2.value = 200;
n2.next = &n3;
n3.value = 300;
n3.next = &n4;
n4.value = 400;
n4.next = 0;


while( list_pointer != 0 ) {
printf("%d\n", list_pointer->value);
list_po in ter = list_pointer->next;
}
}

T hi s program uses a pointer called list_pointer to cycle through the linked list.

For more details , please visit the source site :

http://gd.tuwien.ac.at/la nguag es/c/programming-bbrown/c_086. htm

Answered by shepherd , an ibibo Master, at 6:21 PM on May 30, 2008

Hi,

A linked list program in c with insertion, deletion, display and traversal.

The program is given below-

/*Insertion ,Deletion, Display and Traversal in Binary Search Tree*/
# include
# include

struct node
{
int info;
struct node *lchild;
struct node *rchild;
}*root;

main()
{
int choice,num;
root=NULL;
while(1)
{
printf("\n");
printf("1.Insert\ n");
printf("2.Delete\n");
printf ("3.Inorder Traversal\n");
printf("4.Preorder Traversal\n");
printf("5.Postorder Traversal\n");
printf("6.Display\n ");
printf("7.Quit\n");
printf("E nter your choice : ");
scanf("%d",&choice);

switch (choice)
{
case 1:
printf("Enter the number to be inserted : ");
scanf("%d",&num);
insert(num) ;
break;
case 2:
printf("Enter the number to be deleted : ");
scanf("%d",&num);
del(num);
break;
case 3:
inorder(root);
break;
case 4:
preorder(root);
break;
case 5:
postorder(root);
break;
case 6:
display(root,1);
break;
case 7:
exit();
default:
printf("Wron g choice\n");
}/*End of switch */
}/*End of while */
}/*End of main()*/

find(int item,struct node **par,struct node **loc)
{
struct node *ptr,*ptrsave;

if(root==NULL) /*tree empty*/
{
*loc=NULL;
*par=NULL;
return;
}
if(item==root->info) /*item is at root*/
{
*loc=root;
*par=NULL;
return;
}
/*Initialize ptr and ptrsave*/
if(iteminfo)
ptr=root-> lchild;
else
ptr=root->rchild;
p trsave=root;

while(ptr!=NULL)
{
if(item==ptr->info)
{ *loc=ptr;
*par=ptrsave;
return;
}
ptrsave=ptr;
if(iteminfo)
ptr= ptr->lchild;
else
ptr=ptr->rchild ;
}/*End of while */
*loc=NULL; /*item not found*/
*par=ptrsave;
}/*End of find()*/

insert(int item)
{ struct node *tmp,*parent,*location;
find(item, &parent,&location);
if(location!=N ULL)
{
printf("Item already present");
return;
}

tmp=(stru ct node *)malloc(sizeof(struct node));
tmp->info=item;
tmp->lchi ld=NULL;
tmp->rchild=NULL;

if(p arent==NULL)
root=tmp;
else
if(i teminfo)
parent->lchild=tmp;
else
parent->rchild=tmp;
}/*End of insert()*/

del(int item)
{
struct node *parent,*location;
if(root==NULL)
{
printf("Tree empty");
return;
}

find(item,& parent,&location);
if(location==NU LL)
{
printf("Item not present in tree");
return;
}

if(location- >lchild==NULL && location->rchild==NULL)
case_a(par ent,location);
if(location->lchild !=NULL && location->rchild==NULL)
case_b(par ent,location);
if(location->lchild ==NULL && location->rchild!=NULL)
case_b(par ent,location);
if(location->lchild !=NULL && location->rchild!=NULL)
case_c(par ent,location);
free(location);
}/ *End of del()*/

case_a(struct node *par,struct node *loc )
{
if(par==NULL) /*item to be deleted is root node*/
root=NULL;
else
if(loc==p ar->lchild)
par->lchild=NULL;
els e
par->rchild=NULL;
}/*End of case_a()*/

case_b(struct node *par,struct node *loc)
{
struct node *child;

/*Initialize child*/
if(loc->lchild!=NULL) /*item to be deleted has lchild */
child=loc->lchild;
else /*item to be deleted has rchild */
child=loc->rchild;

if(par==N ULL ) /*Item to be deleted is root node*/
roo

Answered by Ajay Pal , an ibibo Master, at 6:33 AM on May 30, 2008