Question

C++
a. Write a program that uses the function isPalindrome given in example 6-6 (Palindrome). Test your program on the followinng strings: "madam", "abba", "22", "67876", "444244", and "trymeuemyrt"

b. Modify the function isPalindrome of example 6-6 so that when determining weather a string is a palindrome, cases are ignored, that is, uppercase and lowercase letters are considered the same.

Example 6-6:
bool isPalindrome (string str)
{
int length = str.length();
for (int i = 0; i < length / 2; i++)
if (str[i] != str[length - 1 - i];
return false;
return true;
}

Answer 1

Answer:

a) # include <iostream>

# include <conio.h>

# include <stdio.h>

# include <string.h>

using namespace::std;

bool IsPalindrome(const string& str)

{

   if (str.empty())

       return false;

   int i = 0;                // first characters

   int j = str.length() - 1; // last character

   while (i < j)

   {

     

       if (str[i] != str[j])

       {

           return false;

       }

       i++;

       j--;

   }

   return true;

}

int main()

{      

      string str;

      cout<<"Enter the string";

      getline(cin, str);

      bool a= IsPalindrome(str);

      if(a)

      {

          cout<<"Is in palindrome";

      }

      else

      {

          cout<<"Is not in palindrome";

      }

}

b) Modified version of function with full program to discard uppercase or lowercase is as below:

# include <iostream>

# include <conio.h>

# include <stdio.h>

# include <string.h>

using namespace::std;

bool IsPalindrome(const string& str)

{

   if (str.empty())

       return false;

   int i = 0;                // first characters

   int j = str.length() - 1; // last character

   while (i < j)

   {

       char a= tolower(str[i]);

       char b= tolower(str[j]);

       if (a != b)

       {

           return false;

       }

       i++;

       j--;

   }

   return true;

}

int main()

{      

      string str;

      cout<<"Enter the string";

      getline(cin, str);

      bool a= IsPalindrome(str);

      if(a)

      {

          cout<<"Is in palindrome";

      }

      else

      {

          cout<<"Is not in palindrome";

      }

}

Explanation:

Please check the answer section.