sorting programs and algorithms

/*Source code of simple quick sort implementation using array ascending order in c programming language*/
#include<stdio.h>
#include<conio.h>

void quicksort(int [10],int,int);

void main()
{
  int size,i;
  int a[]={5,9,7,2,4};
  n=5;
  clrscr();
/*  printf("Enter size of the array: ");
  scanf("%d",&n);

  printf("Enter %d elements: ",size);
  for(i=0;i<n;i++)
    scanf("%d",&a[i]);
  */
  quicksort(x,0,n-1);

  printf("Sorted elements: ");
  for(i=0;i<n;i++)
    printf(" %d",a[i]);
    getch();
}
void swap(int *x, int *y)
{
 int temp;
 temp=*x;
 *x=*y;
 *y=temp;
}

void quicksort(int x[10],int f,int l)
{
 int pivot,j,temp,i;
 if(f<last)
 {
   p=f;
   i=f;
   j=l;
   while(i<j)
   {
     while(x[i]<=x[p]&&i<l)
i++;
     while(x[j]>x[p])
j--;
     if(i<j)
     {
       swap(&x[i],&x[j]);
     }
    }//while
    swap(&x[p],&x[j]);
    quicksort(x,f,j-1);
    quicksort(x,j+1,l);
 }//if
}
/*
Output:
Enter size of the array: 5
Enter 5 elements: 3 8 0 1 2
Sorted elements: 0 1 2 3 8*/

Linked List

//WAP TO DEMONSTRATE THE OPERATIONS ON Single Linked List
#include<stdio.h>
#include<conio.h>
#include<alloc.h>
struct sl_node
{
 int m;
 struct sl_node *link;
}*start=NULL;
typedef struct sl_node node;
void create()
{
 int n,i,marks;
 node *temp,*r;
 printf("enter the no of elements of linked list\n");
 scanf("%d",&n);
 for(i=0;i<n;i++)
 {
  printf("enter the marks\n");
  scanf("%d",&marks);
  temp=(node*)malloc(sizeof(node));
  temp->m=marks;
  //temp=temp->link;
 //}
  if(start==NULL)
  {
   temp->link=NULL;
   start=temp;
  }
  else
  {
   r=start;
   while(r->link!=NULL)
   {
    r=r->link;
   }
    temp->link=r->link;
    r->link=temp;
  // }//while
  } //else
 }//create
 }
void addbeg(int marks)
{
  node* temp;
  temp=(node*)malloc(sizeof(node));
  temp->m=marks;
  temp->link=start;
  start=temp;
}
void addend(int marks)
{
 node *temp,*r;
 temp=start;
 while(temp->link!=NULL)
 {
  temp=temp->link;
  r=(node*)malloc(sizeof(node));
  r->m=marks;
  r->link=temp->link;
  temp->link=r;
 }
}
//add after specified node number
void addafter(int marks,int pos)
{
 int i;
 node* temp,*r;
 temp=start;
 for(i=1;i<pos;i++)
 temp=temp->link;
 r=(node*)malloc(sizeof(node));
 r->m=marks;
 r->link=temp->link;
 temp->link=r;
 }


void display()
{
 node *temp=start;
 if(temp==NULL)

  printf("it is empty\n");
 else
 {

  printf("sll follows\n");

  while(temp!=NULL)
  {
   printf("%d->",temp->m);
   temp=temp->link;
  }//while
 }//else
}//disp()
void del(int marks)
{
 node *temp,*old;
 temp=start;
 while(temp!=NULL)
 {
  if(temp->m==marks)
  {
   if(temp==start)
    start=start->link;
   else
    old->link=temp->link;
   printf("%d is deleted from s.l\n",marks);
   free(temp);
  }
  else
  {
   old=temp;
   temp=temp->link;
  } //else
 } //while
 printf("%d is not found in the s.l\n",marks);
}//del()
void destroy()
{
 node *temp;
 while(start!=NULL)
 {
  temp=start->link;
  free(start);
  start=temp;
 }
 printf("linked list is destroyed\n");
}
void menu()
{
 printf("1.insert at the begining of ll\n");
 printf("2.insert at the end\n");
 printf("3.displaying \n");
 printf("4.delete node\n");
 printf("5.destroy the s.l\n");
 printf("6.exit\n");
}
void main()
{
 int ch,pos,marks,c,count;
 node *start=NULL;
 void create();
 void addbeg(int);
// void addafter(int,int);
 void addend(int);
 void display();
 void del(int);
 void destroy();
 clrscr();
 create();
 menu();

 do
 {
  printf("enter ur choice\n");
  scanf("%d",&ch);
  switch(ch)
  {
   case 1:{
printf("enter the marks\n");
scanf("%d",&marks);
addbeg(marks);
break;
       }
   case 2:{
printf("enter the marks\n");
scanf("%d",&marks);
addend(marks);
break;
       }
/*   case 3:{
printf("enter the marks\n");
scanf("%d",&marks);
addafter(marks);
break;
       }
*/
    case 3:{
display();
break;
}
    case 4:{
printf("enter the marks\n");
scanf("%d",&marks);
del(marks);
break;
       }
    case 5:{
destroy();
break;
}
    default :
      exit();
  }//switch()

}while(ch!=6);
}


#include<stdio.h>
#include<conio.h>
#include<alloc.h>
struct ll
{
 int data;
 struct ll* link;
};
typedef struct ll node_type;

//creation of a linked list
node_type* sl_create()//this fun has no input but output first
{
 node_type *temp,*t,*k,*first;
 int x;
 first=(node_type*)malloc(sizeof(node_type));
 temp=first;
 printf("enter the data fields of all the nodes\n");
 while(scanf("%d",&x)!=EOF)
 //EOF MEANS CONTROL +Z
 {
  t=(node_type*)malloc(sizeof(node_type));
  t->data=x;//filing data field
  temp->link=t;
  temp=temp->link; //or t;//movin temp to latest node
 }
 temp->link=NULL;//fillin the link field of last node
 k=first;//put k pointer to dummy node to delete it by free
 first=first->link;//first come to action first node
 free(k);//
 return(first);
}
//displaying linked list
void ll_print(node_type *first)
{
 node_type *temp;
 for(temp=first;temp!=NULL;temp=temp->link)
 {
  printf("%d\t %u\n",temp->data,temp->link);//%u=address or position
 }
}


//concatination two linked lists
node_type* concatinate(node_type* first1,node_type* first2)
{
 node_type *temp;
 if((first1==NULL)&&(first2==NULL))
 {
  return(NULL);
 }
 else
 if((first1==NULL)&&(first2==NULL))
  return(first2);
 else if((first1!=NULL)&&(first2==NULL))
  return(first1);
 else
 { //putin a pointer temp &moving temp until temp link!=null
  for(temp=first1;temp->link!=NULL;temp=temp->link)
  {
   ;
  }
  temp->link=first2;
  return(first1);
 }
}

void main()
{
 node_type *first1,*first2,*first3;
 node_type* sl_create();
 node_type* concatinate(node_type* first1,node_type* first2);
 first1=sl_create();
 first2=sl_create();
 first3=concatinate(first1,first2);
 ll_print(first3);
}
*******************************************************************

//count a linked list
#include<stdio.h>
#include<conio.h>
#include<alloc.h>
struct ll
{
 int data;
 struct ll* link;
};
typedef struct ll node_type;

//creation of a linked list
node_type* sl_create()//this fun has no input but output first
{
 node_type *temp,*t,*k,*first;
 int x;
 first=(node_type*)malloc(sizeof(node_type));
 temp=first;
 printf("enter the data fields of all the nodes\n");
 while(scanf("%d",&x)!=EOF)
 //EOF MEANS CONTROL +Z
 {
  t=(node_type*)malloc(sizeof(node_type));
  t->data=x;//filing data field
  temp->link=t;
  temp=temp->link; //or t;//movin temp to latest node
 }
 temp->link=NULL;//fillin the link field of last node
 k=first;//put k pointer to dummy node to delete it by free
 first=first->link;//first come to action first node
 free(k);//
 return(first);
}
//write a c function to find the no of nodes (ie. lenght of link.list
int count(node_type *first)
{
 node_type *temp;
 int ctr;
 ctr=0;
 for(temp=first;temp!=NULL;temp=temp->link)
 {
  ctr++;
 }
 return(ctr);
}


//displaying linked list
void ll_print(node_type *first)
{
 node_type *temp;
 for(temp=first;temp!=NULL;temp=temp->link)
 {
  printf("%d\t %u\n",temp->data,temp->link);//%u=address or position
 }
}


node_type * reverse(node_type *first)
{
 node_type *p,*q,*r;
 p=first;
 q=NULL;
 r=NULL;
 while(p!=NULL)
 {
  r=q;//a pointer moved one step right
  q=p;
  p=p->link;
  q->link=r;//addres of previous store NULL stored in r
   //bcoz of this only links are changed
 }
 first=q;
 return(first);
}

void main()
{
 node_type *first;
 node_type* sl_create();
 int ans,count();
 void ll_print();
 first=sl_create();//linked list created
 ans=count(first);
 printf("no of nodes is %d\n",ans);
}
 ll_print(first);//displaying
}
*********************************************************************************

//reversing a linked list
#include<stdio.h>
#include<conio.h>
#include<alloc.h>
struct ll
{
 int data;
 struct ll* link;
};
typedef struct ll node_type;
//creation of a linked list
node_type* sl_create()//this fun has no input but output first
{
 node_type *temp,*t,*k,*first;
 int x;
 first=(node_type*)malloc(sizeof(node_type));
 temp=first;
 printf("enter the data fields of all the nodes\n");
 while(scanf("%d",&x)!=EOF)
 //EOF MEANS CONTROL +Z
 {
  t=(node_type*)malloc(sizeof(node_type));
  t->data=x;//filing data field
  temp->link=t;
  temp=temp->link; //or t;//movin temp to latest node
 }
 temp->link=NULL;//fillin the link field of last node
 k=first;//put k pointer to dummy node to delete it by free
 first=first->link;//first come to action first node
 free(k);//
 return(first);
}
//displaying linked list
void ll_print(node_type *first)
{
 node_type *temp;
 for(temp=first;temp!=NULL;temp=temp->link)
 {
  printf("%d\t %u\n",temp->data,temp->link);//%u=address or position
 }
}


node_type * reverse(node_type *first)
{
 node_type *p,*q,*r;
 p=first;
 q=NULL;
 r=NULL;
 while(p!=NULL)
 {
  r=q;//a pointer moved one step right
  q=p;
  p=p->link;
  q->link=r;//addres of previous store NULL stored in r
   //bcoz of this only links are changed
 }
 first=q;
 return(first);
}

void main()
{
 node_type *first,*reverse();
 node_type* sl_create();
 void ll_print();
 first=sl_create();//linked list created
 first=reverse(first);//function call
 ll_print(first);//displaying
}