Chapter 14, Problem 1P

Explanation of Solution

Recursive function for nth Fibonacci numbers:

The recursive function for nth Fibonacci number is shown below:

/* Function definition for compute nth Fibonacci number */

int recursiveFibFunction(int n)

{

       /* If "n" is less than or equal to "1", then */

       if (n <= 1)

              //Return value of "n"

              return n;

  /* Otherwise Recursively call the function "recursiveFibFunction" */

  return recursiveFibFunction(n-1) + recursiveFibFunction(n-2);

}

Explanation:

The above function is used to compute the nth Fibonacci numbers.

• In this function, first check the value of “n”. If the value of “n” is less than or equal to “1” that is value of “n” is either “1” or “0”, then returns the given “n” value.
• Otherwise, recursively call the function “recursiveFibFunction”.

Complete executable code:

The complete code is implemented for Fibonacci number is shown below:

//Header file

#include<iostream>

//For standard input and output

using namespace std;

//Function declaration for "recursiveFibFunction" function

int recursiveFibFunction(int n);

//Main function

int main ()

{

       //Initializes the number to "8"

       int number = 8;

  /* Dispay fibonacci number by calling the function "recursiveFibFunction" */

  cout << number << "th Fibonacci number is: "<< recursiveFibFunction(number) << endl;

       return 0;

}

/* Function definition for compute nth Fibonacci number */

int recursiveFibFunction(int n)

{

       /* If "n" is less than or equal to "1", then */

       if (n <= 1)

              //Return value of "n"

              return n;

  /* Otherwise Recursively call the function "recursiveFibFunction" */

  return recursiveFibFunction(n-1) + recursiveFibFunction(n-2);

}

Sample Output

8th Fibonacci number is: 21