Chapter 3, Problem 20C

Explanation of Solution

Program code:

//include the required header files

#include <stdio.h>

#include <string.h>

Using namespace std;

//define a function is_palindrome()

int is_palindrome(char *str, int length)

{

//if the condition is true

if (str >= str + length)

{

//return 1

return 1;

}

//if the condition is false

else

{

//if the condition is true

if (!((str[0] >= 'a' && str[0] <= 'z') || (str[0] >= 'A' && str[0] <= 'Z')))

//return

return is_palindrome(str + 1, length - 1);

//if the condition is true

if (!((str[length - 1] >= 'a' && str[length - 1] <= 'z') ||

(str[length - 1] >= 'A' && str[length - 1] <= 'Z')))

//call the method by itself

return is_palindrome(str, length - 1);

//return the value

return str[0] == str[length - 1] && is_palindrome(str + 1, length - 2);

}

}

//define main function

int main()

{

//print 1 if palinddrome

cout<<"...