Lab-2 - Sorting using fork().c

# include<stdio.h>
# include <stdlib.h>
# include<sys/types.h>
# include<unistd.h>


int split ( int a[ ], int lower, int upper )
{
    int i, p, q, t ;
    p = lower + 1 ;
    q = upper ;
    i = a[lower] ;
    while ( q >= p )
    {
        while ( a[p] < i )
            p++ ;
        while ( a[q] > i )
            q-- ;
        if ( q > p )
        {
            t = a[p] ;
            a[p] = a[q] ;
            a[q] = t ;
        }
    }
    t = a[lower] ;
    a[lower] = a[q] ;
    a[q] = t ;
    return q ;
}

void quickSort(int a[],int lower, int upper)
{
    int i ;
    if ( upper > lower )
    {
        i = split ( a, lower, upper ) ;
        quickSort ( a, lower, i - 1 ) ;
        quickSort ( a, i + 1, upper ) ;
    }
}

   
void mergeSort(int arr[],int low,int mid,int high)
{
    
    int i,j,k,l,b[20];
    l=low;
    i=low;
    j=mid+1;
    while((l<=mid)&&(j<=high))
    {
        if(arr[l]<=arr[j])
        {
            b[i]=arr[l];
            l++;
        }
        else
        {
            b[i]=arr[j];
            j++;
        }
        i++;
    }
    if(l>mid)
    {
        for(k=j;k<=high;k++)
        {
            b[i]=arr[k];
            i++;
        }
    }
    else
    {
        for(k=l;k<=mid;k++)
        {
            b[i]=arr[k];
            i++;
        }
    }
    for(k=low;k<=high;k++)
    {
        arr[k]=b[k];
    }
}

void partition(int arr[],int low,int high)
{
    int mid;
    if(low<high)
    {
        double temp;
        mid=(low+high)/2;
        partition(arr,low,mid);
        partition(arr,mid+1,high);
        mergeSort(arr,low,mid,high);
    }
}

void display(int a[],int size)
{
    int i;
    for(i=0;i<size;i++)
    {
        printf("%d\t\t",a[i]);
    }
    printf("\n");
}

int main()
{
    int pid, child_pid;
    int size,i,status;
    printf("Enter the number of Integers to Sort::::\t");
    scanf("%d",&size);
    int a[size];
    int pArr[size];
    int cArr[size];
    for(i=0;i<size;i++)
    {
        printf("Enter number %d:",(i+1));
        scanf("%d",&a[i]);
        pArr[i]=a[i];
        cArr[i]=a[i];
    }
    printf("Your Entered Integers for Sorting\n");
    display(a,size);
    pid=getpid();   
    printf("Current Process ID is : %d\n",pid);
    printf("[ Forking Child Process ... ] \n");   
    child_pid=fork();     
    if( child_pid < 0)
    {
        printf("\nChild Process Creation Failed!!!!\n");
        exit(-1);
    }
    else if( child_pid==0) 
    {
        printf("\nThe Child Process\n");
        printf("\nChild process is %d",getpid());
        printf("\nParent of child process is %d\n",getppid());
        printf("Child is sorting the list of Integers by QUICK SORT::\n");
        quickSort(cArr,0,size-1);
        printf("The sorted List by Child::\n");
        display(cArr,size);
        printf("Child Process Completed ...\n");
        sleep(10);
    }
    else 
    {
        printf("Parent process %d started\n",getpid());
        printf("Parent of parent is %d\n",getppid());
        sleep(30);
        printf("\nThe Parent Process\n");
        printf("\nParent %d is sorting the list of Integers by MERGE SORT\n",pid);
        partition(pArr,0,size-1);
        printf("The sorted List by Parent::\n");
        display(pArr,size);
        wait(&status);
        printf("Parent Process Completed ...\n");
    } 
    return 0;
}