Malloc

GXTechno Tags: c, data, structure, malloc

#include<stdio.h>
#include<conio.h>
#include<malloc.h>
struct node
{
int info;
struct node *next;
};
typedef struct node NODE;
NODE *start;
void createmptylist(NODE **start)
{
*start=(NODE *)NULL;
}
void traversinorder(NODE *start)
{
while(start != (NODE *) NULL)
{
printf("%d\n",start->info);
start=start->next;
}
}
void insertatbegin(int item)
{
NODE *ptr;
ptr=(NODE *)malloc(sizeof(NODE));
ptr->info=item;
if(start==(NODE *)NULL)
ptr->next=(NODE *)NULL;
else
ptr->next=start;
start=ptr;
}
void insert_at_end(int item)
{
NODE *ptr,*loc;
ptr=(NODE *)malloc(sizeof(NODE));
ptr->info=item;
ptr->next=(NODE *)NULL;
if(start==(NODE*)NULL)
start=ptr;
else
{
loc=start;
while(loc->next!=(NODE *)NULL)
loc=loc->next;
loc->next=ptr;
}
}

void dele_beg(void)
{
NODE *ptr;
if(start==(NODE *)NULL)
return;
else
{
ptr=start;
start=(start)->next;
free(ptr);
}
}
void dele_end(NODE *start)
{
NODE *ptr,*loc;
if(start==(NODE *)NULL)
return;
else if((start)->next==(NODE *)NULL)
{
ptr=start;
start=(NODE *)NULL;
free(ptr);
}
else
{
loc=start;
ptr=(start)->next;
while(ptr->next!=(NODE *)NULL)
{
loc=ptr;
ptr=ptr->next;
}
loc->next=(NODE *)NULL;
free(ptr);
}
}
void insert_spe(NODE *start,int item)
{
NODE *ptr,*loc;
int temp,k;
for(k=0,loc=start;k<temp;k++)
{
loc=loc->next;
if(loc==NULL)
{
printf("node in the list at less than one\n");
return;
}
}
ptr=(NODE *)malloc(sizeof(NODE));
ptr->info=item;
ptr->next=loc->next;;
loc->next=ptr;
}
dele_spe(NODE *start)
{
NODE *ptr,*loc;
int temp;
printf("\nEnter the which element do you want to delete\n");
scanf("%d",&temp);
ptr=start;
if(start==NULL)
{
printf("Empty list\n");
return;
}
else
{
loc=ptr;
while(ptr!=NULL)
{
if(ptr->info==temp)
{
loc->next=ptr->next;
free(ptr);
return;
}
loc=ptr;
ptr=ptr->next;
}
}
}
void main()
{
int choice,item,after;
char ch;
clrscr();
createmptylist(start);
do
{
printf("1.Insert element at begin \n");
printf("2. insert element at end positon\n");
printf("3. insert specific the position\n");
printf("4.travers the list in order\n");
printf("5. delete from the begin\n");
printf("6. delete from the last\n");
printf("7. delete the element from the specific position\n");
printf("8. exit\n");
printf("enter your choice\n");
scanf("%d",&choice);
switch(choice)
{
case 1: printf("Enter the item\n");
    scanf("%d",&item);
    insertatbegin(item);
    break;
case 2:  printf("Enter the item\n");
    scanf("%d",&item);
    insert_at_end(item);
    break;
case 3: printf("Enter the item\n");
    scanf("%d",&item);
    insert_spe(start,item);
    break;
case 4: printf("\ntravers the list\n");
    traversinorder(start);
    break;
case 5: printf("Delete the item\n");
    dele_beg();
    break;
case 6: printf("Delete the element\n");
    dele_end(start);
    break;
case 7: printf("Delete the element");
    dele_spe(start);
    break;
case 8: return;
}
fflush(stdin);
printf("do your want continous\n");
scanf("%c",&ch);
}while((ch='y')||(ch='y'));
getch();
}

/*output of the program*/
2. insert element at end positon
3. insert specific the position
4.travers the list in order
5. delete from the begin
6. delete from the last
7. delete the element from the specific position
8. exit
enter your choice
1
Enter the item
2
do your want continous
y
1.Insert element at begin
2. insert element at end positon
3. insert specific the position
4.travers the list in order
5. delete from the begin
6. delete from the last
7. delete the element from the specific position
8. exit
enter your choice
2
Enter the item
3
do your want continous
y
1.Insert element at begin
2. insert element at end positon
3. insert specific the position
4.travers the list in order
5. delete from the begin
6. delete from the last
7. delete the element from the specific position
8. exit
enter your choice
5
Delete the item
do your want continous
y
1.Insert element at begin
2. insert element at end positon
3. insert specific the position
4.travers the list in order
5. delete from the begin
6. delete from the last
7. delete the element from the specific position
8. exit
enter your choice