Question

Q1) Write a program to implement the quick sort algorithm in a one dimensional array?

Q2) Write a program to implement the merge sort algorithm in a one dimensional array?

Answer 1

Hello I am adding code for both program in C

Please go through it

Quicksort.c

#include<stdio.h>
void quicksort(int number[25],int first,int last){
   int i, j, pivot, temp;

   if(first<last){
      pivot=first;
      i=first;
      j=last;

      while(i<j){
         while(number[i]<=number[pivot]&&i<last)
            i++;
         while(number[j]>number[pivot])
            j--;
         if(i<j){
            temp=number[i];
            number[i]=number[j];
            number[j]=temp;
         }
      }

      temp=number[pivot];
      number[pivot]=number[j];
      number[j]=temp;
      quicksort(number,first,j-1);
      quicksort(number,j+1,last);

   }
}

int main(){
   int i, count, number[25];

   printf("How many elements are u going to enter?: ");
   scanf("%d",&count);

   printf("Enter %d elements: ", count);
   for(i=0;i<count;i++)
      scanf("%d",&number[i]);

   quicksort(number,0,count-1);

   printf("Order of Sorted elements: ");
   for(i=0;i<count;i++)
      printf(" %d",number[i]);

   return 0;
}

Output

Mergesort.c

#include<stdio.h>
 
void mergesort(int a[],int i,int j);
void merge(int a[],int i1,int j1,int i2,int j2);
 
int main()
{
        int a[30],n,i;
        printf("Enter no of elements:");
        scanf("%d",&n);
        printf("Enter array elements:");
        
        for(i=0;i<n;i++)
                scanf("%d",&a[i]);
                
        mergesort(a,0,n-1);
        
        printf("\nSorted array is :");
        for(i=0;i<n;i++)
                printf("%d ",a[i]);
                
        return 0;
}
 
void mergesort(int a[],int i,int j)
{
        int mid;
                
        if(i<j)
        {
                mid=(i+j)/2;
                mergesort(a,i,mid);             //left recursion
                mergesort(a,mid+1,j);   //right recursion
                merge(a,i,mid,mid+1,j); //merging of two sorted sub-arrays
        }
}
 
void merge(int a[],int i1,int j1,int i2,int j2)
{
        int temp[50];   //array used for merging
        int i,j,k;
        i=i1;   //beginning of the first list
        j=i2;   //beginning of the second list
        k=0;
        
        while(i<=j1 && j<=j2)     //while elements in both lists
        {
                if(a[i]<a[j])
                        temp[k++]=a[i++];
                else
                        temp[k++]=a[j++];
        }
        
        while(i<=j1) //copy remaining elements of the first list
                temp[k++]=a[i++];
                
        while(j<=j2) //copy remaining elements of the second list
                temp[k++]=a[j++];
                
        //Transfer elements from temp[] back to a[]
        for(i=i1,j=0;i<=j2;i++,j++)
                a[i]=temp[j];
}

Output