Chapter 14, Problem 5P

Explanation of Solution

Recursive function for checking palindrome:

The recursive function definition for checking the given string is a palindrome or not is shown below:

/* Function definition for checkPalindromeRecursion function */

bool checkPalindromeRecursion(string str)

{

      /* If length is "0" or "1", then return "true" */

      if(str.length() == 0 || str.length() == 1)

            return true;

        /* Check the first character*/

        if(isdigit(str.at(0)))

        {

     /* If the first character is equal to the last character, then */

              if(str.at(0) == str.at(str.length()-1))

     /* Recursively call the function "checkPalindromeRecursion" with remaining characters */

       return checkPalindromeRecursion(str.substr(1, str.length()-2));

        }

        //Otherwise

        else

        {

              //For checking the lower characters

     if(tolower(str.at(0)) == tolower(str.at(str.length()-1)))

     return checkPalindromeRecursion(str.substr(1, str.length()-2));

        }

        //Otherwise returns "false"

        return false;

}

Explanation:

The above function is used to check the given string is a palindrome or not using recursive function.

• If the length of string is “0” or “1”, then returns “true”.
• Check the first digit of given string.  If it is, then check if the first character is equal to the last character, then recursively call the function “checkPalindromeRecursion” for remaining characters in given string.
• Otherwise, return “false” that is for not palindrome string.

Complete Executable code:

The complete code is implemented for checking the palindrome is shown below:

//Header file

#include <iostream>

#include <iomanip>

//For standard input and output

using namespace std;

/* Function definition for checkPalindromeRecursion function */

bool checkPalindromeRecursion(string str)

{

      /* If length is "0" or "1", then return "true" */

      if(str...