MERGE SORT

/* merge sort*/

#include<stdio.h>

#define MAX 20

int a[MAX];

void merge(int low,int mid,int high)

{

    int temp[MAX];

    int i=low;

    int j=mid+1;

    int k=low;

    while((i<=mid)&&(j<=high))

    {

        if(a[i]<=a[j])

            temp[k++]=a[i++];

        else

            temp[k++]=a[j++];

    }

    while(i<=mid)

        temp[k++]=a[i++];

    while(j<=high)

        temp[k++]=a[j++];

    for(i=low;i<=high;i++)

        a[i]=temp[i];

}

void merge_sort(int low,int high)

{

    int mid;

    if(low!=high)

    {

        mid=(low+high)/2;

        merge_sort(low,mid);

        merge_sort(mid+1,high);

        merge(low,mid,high);

    }

}

main()

{

    int i,n;

    printf("\nEnter the number of elements:");

    scanf("%d",&n);

    for(i=0;i<n;i++)

    {

        printf("\nEnter element %d:",i+1);

        scanf("%d",&a[i]);

    }

    printf("\nUnsorted list is:\n ");

    for(i=0;i<n;i++)

        printf("%d\t",a[i]);

    merge_sort(0,n-1);

    printf("\nSorted list is:\n");

    for(i=0;i<n;i++)

        printf("%d\t",a[i]);

}

                             .......OUTPUT....

Enter the number of elements:5

Enter element 1:6

Enter element 2:3

Enter element 3:9

Enter element 4:4

Enter element 5:2

Unsorted list is:

 6      3       9       4       2

Sorted list is:

2       3       4       6       9

QUICK SORT

/* quick sort*/

#include<stdio.h>

int a[20],n;

void sort(int a[],int lb,int ub)

{

          int p;

          if(lb>=ub)

                   return;

          p=partetion(a,lb,ub);

          sort(a,lb,p-1);

          sort(a,p+1,ub);

}

int partetion(int a[],int lb,int ub)

{

          int down,up,key,t;

          down=lb;

          up=ub;

          key=a[lb];

          while(down<up)

          {

                   while((key>=a[down]) &&(down<up))

                             down++;

                   while(key<a[up])

                             up--;

                   if(down<up)

                   {

                             t=a[down];

                             a[down]=a[up];

                             a[up]=t;

                   }

          }

          a[lb]=a[up];

          a[up]=key;

          return up;

}

main()

{

          int i;

          printf("enter the number of elements:");

          scanf("%d",&n);

          for(i=1;i<=n;i++)

          {

                   printf("enter element %d:",i);

                   scanf("%d",&a[i]);

          }

          printf("unsorted list:");

          for(i=1;i<=n;i++)

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

          sort(a,1,n);

          printf("\nsorted list:\n");

          for(i=1;i<=n;i++)

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

}

                   .......OUTPUT.......

enter the number of elements:5

enter element 1:6

enter element 2:9

enter element 3:3

enter element 4:1

enter element 5:7

unsorted list:  6       9       3       1       7

sorted list:

1       3       6       7       9