C Exercises: Merge two arrays of same size sorted in decending order

C Array: Exercise-7 with Solution

Write a program in C to merge two arrays of the same size sorted in descending order.

Visual Presentation:

Sample Solution:

C Code:

#include <stdio.h>

int main()
{
    int arr1[100], arr2[100], arr3[200];
    int s1, s2, s3;
    int i, j, k;
	
	
       printf("\n\nMerge two arrays of same size sorted in decending order.\n");
       printf("------------------------------------------------------------\n");	
	   
       printf("Input the number of elements to be stored in the first array :");
       scanf("%d",&s1);
   
       printf("Input %d elements in the array :\n",s1);
       for(i=0;i<s1;i++)
            {
	      printf("element - %d : ",i);
	      scanf("%d",&arr1[i]);
	    }


       printf("Input the number of elements to be stored in the second array :");
       scanf("%d",&s2);
   
       printf("Input %d elements in the array :\n",s2);
       for(i=0;i<s2;i++)
            {
	      printf("element - %d : ",i);
	      scanf("%d",&arr2[i]);
	    }

    /* size of merged array is size of first array and  size of second array */
    s3 = s1 + s2;
/*----------------- insert in the third array------------------------------------*/
    for(i=0;i<s1; i++)
        {
            arr3[i] = arr1[i];
         }
     for(j=0;j<s2; j++)
        {
            arr3[i] = arr2[j];
            i++; 
        }
/*----------------- sort the array in decending order ---------------------------*/
   for(i=0;i<s3; i++)
        {
           for(k=0;k<s3-1;k++)
             {
         
                if(arr3[k]<=arr3[k+1])
                 {
                   j=arr3[k+1];
                   arr3[k+1]=arr3[k];
                   arr3[k]=j;
                 }  
              }
         }                      

/*--------------- Prints the merged array ------------------------------------*/
     printf("\nThe merged array in decending order is :\n");
    for(i=0; i<s3; i++)
    {
        printf("%d   ", arr3[i]);
    }
	printf("\n\n");
	return 0;
}

Sample Output:

Merge two arrays of same size sorted in decending order.                                                      
------------------------------------------------------------                                                  
Input the number of elements to be stored in the first array :3                                               
Input 3 elements in the array :                                                                               
element - 0 : 1                                                                                               
element - 1 : 2                                                                                               
element - 2 : 3                                                                                               
Input the number of elements to be stored in the second array :3                                              
Input 3 elements in the array :                                                                               
element - 0 : 1                                                                                               
element - 1 : 2                                                                                               
element - 2 : 3                                                                                               
                                                                                                              
The merged array in decending order is :                                                                      
3   3   2   2   1   1 

Explanation:

 printf("Input the number of elements to be stored in the first array :");
       scanf("%d",&s1);
   
       printf("Input %d elements in the array :\n",s1);
       for(i=0;i<s1;i++)
            {
	      printf("element - %d : ",i);
	      scanf("%d",&arr1[i]);
	    }


       printf("Input the number of elements to be stored in the second array :");
       scanf("%d",&s2);
   
       printf("Input %d elements in the array :\n",s2);
       for(i=0;i<s2;i++)
            {
	      printf("element - %d : ",i);
	      scanf("%d",&arr2[i]);
	    }

    /* size of merged array is size of first array and  size of second array */
    s3 = s1 + s2;
/*----------------- insert in the third array------------------------------------*/
    for(i=0;i<s1; i++)
        {
            arr3[i] = arr1[i];
         }
     for(j=0;j<s2; j++)
        {
            arr3[i] = arr2[j];
            i++; 
        }
/*----------------- sort the array in decending order ---------------------------*/
   for(i=0;i<s3; i++)
        {
           for(k=0;k<s3-1;k++)
             {
         
                if(arr3[k]<=arr3[k+1])
                 {
                   j=arr3[k+1];
                   arr3[k+1]=arr3[k];
                   arr3[k]=j;
                 }  
              }
         }                      

/*--------------- Prints the merged array ------------------------------------*/
     printf("\nThe merged array in decending order is :\n");
    for(i=0; i<s3; i++)
    {
        printf("%d   ", arr3[i]);
    }

In the above code -

• The first printf statement prompts the user to input the number of elements they want to store in the first array and stores it in the variable s1 using scanf.
• The second printf statement asks the user to input s1 number of elements into the first array arr1 using a for loop, and stores each input in the corresponding index of the array arr1[i].
• The third printf statement prompts the user to input the number of elements they want to store in the second array and stores it in the variable s2 using scanf.
• The fourth printf statement asks the user to input s2 number of elements into the second array arr2 using a for loop, and stores each input in the corresponding index of the array arr2[i].
• The next for loop then combines the two arrays into a single array arr3 by copying the elements of arr1 into arr3, and then copying the elements of arr2 into arr3 starting from the index after the last element of arr1.
• The next for loop sorts the elements in arr3 in descending order using a bubble sort algorithm.
• Finally, the last printf statement prints out the merged and sorted arr3.

Flowchart:

C Programming Code Editor:

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