Question

**IN C***

*

In this lab, you will write a program with three recursive functions you will call in your main. For the purposes of this lab, keep all functions in a single source file: main.c Here are the three functions you will write. For each function, the output example is for this array: int array[ ] = { 35, 25, 20, 15, 10 }; • Function 1: This function is named printReverse(). It takes in an array of integers and an index in the array. It prints out the contents of that array in reverse order. It will print out the index, colon, space, and array value then new line. When it reaches the beginning, print out the message Beginning of array. The initial function call will pass the array in and the last index. 4: 10 3: 15 2: 20 1: 25 0: 35 Beginning of array • Function 2: This function is named calculateSum( ). It takes in an array of integers with the length of that array. It will compute and return the sum recursively. The initial function call will pass the array in and the last index. • Function 3: This function is named countOdds(). It takes in an array of integers with the length of that array as parameters. It returns a count of how many odd numbers there are, which will be counted recursively. The initial function call will pass the array in and the last index. Write the main() that will do the following: • Your main function will call each of these three functions and print out the results. • For the array, declare an array of integers. You can choose the size and ask the user to enter the values. Assume they will always enter a valid value.

Answer 1

Source Code:

#include<stdio.h> /*main function*/ int main(void) { /*variable*/ int n, i, a[100], sum=0, oddcount; /*function prototypes*/ void printReverse(int[], int); int calculateSum(int[],int); int countOdds(int[], int); /*read size of the array from the user*/ printf("Enter the size of the array: "); scanf("%d",&n); /*read elements of array from the user*/ printf("Enter the elements:\n"); for(i=0;i<n;i++) scanf("%d",&a[i]); /*function calls*/ printf("array in reverse order: \n"); printReverse(a, n-1);

sum=calculateSum(a, n-1); /*print sum*/ printf("\nThe sum of the elements is: %d", sum); oddcount=countOdds(a,n-1); /*print oddCount*/ printf("\nThe count of odd numbers is: %d", oddcount); return 0; } /*function definition*/ void printReverse(int a[], int n) { /*check for valid index*/ if(n>=0) { /*print element*/ printf("%d: %d\n", n, a[n]); /*recursive call*/ printReverse(a, n-1); } else

printf("Beginning of array"); /*function definition*/ int calculateSum(int a[], int n) { /*check for valid index*/ if(n>=0) { /*calculate sum and recursive call*/ return a[n]+calculateSum(a, n-1); } else return 0; } /*function definition*/ int countOdds(int a[], int n) { int c=0; /*check for valid index*/ if(n>=0)

{ /*check for odd number*/ if(a[n]%2!=0) { c=1; /*recursive call*/ return c+countOdds(a, n-1); } /*if even then call recursively*/ else countOdds(a, n-1); } else return 0; }

Output:

C:\Users\Kumar Reddi\Desktop\trail.exe Enter the size of the array: 5 Enter the elements: 35 25 20 15 10 array in reverse order: 4: 10 3: 15 2: 20 1: 25 0: 35 Beginning of array The sum of the elements is: 105 The count of odd numbers is: 3 Process exited after 41.96 seconds with return value o Press any key to continue.

Code in text format (See above images of code for indentation)

#include<stdio.h>
/*main function*/
int main(void)
{
   /*variable*/
   int n,i,a[100],sum=0,oddcount;
   /*function prototypes*/
   void printReverse(int[],int);
   int calculateSum(int[],int);
   int countOdds(int[],int);
   /*read size of the array from the user*/
   printf("Enter the size of the array: ");
   scanf("%d",&n);
   /*read elements of array from the user*/
   printf("Enter the elements:\n");
   for(i=0;i<n;i++)
       scanf("%d",&a[i]);
   /*function calls*/
   printf("array in reverse order:\n");
   printReverse(a,n-1);
   sum=calculateSum(a,n-1);
   /*print sum*/
   printf("\nThe sum of the elements is: %d",sum);
   oddcount=countOdds(a,n-1);
   /*print oddCount*/
   printf("\nThe count of odd numbers is: %d",oddcount);
   return 0;
}
/*function definition*/
void printReverse(int a[],int n)
{
   /*check for valid index*/
   if(n>=0)
   {
       /*print element*/
       printf("%d: %d\n",n,a[n]);
       /*recursive call*/
       printReverse(a,n-1);
   }
   else
       printf("Beginning of array");
}
/*function definition*/
int calculateSum(int a[],int n)
{
   /*check for valid index*/
   if(n>=0)
   {
       /*calculate sum and recursive call*/
       return a[n]+calculateSum(a,n-1);
   }
   else
       return 0;
}
/*function definition*/
int countOdds(int a[],int n)
{
   int c=0;
   /*check for valid index*/
   if(n>=0)
   {
       /*check for odd number*/
       if(a[n]%2!=0)
       {
           c=1;
           /*recursive call*/
           return c+countOdds(a,n-1);
       }
       /*if even then call recursively*/
       else
           countOdds(a,n-1);
   }
   else
       return 0;
}