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:

#include <iostream>

#include <array>

using namespace std;

bool isPalindrome(string str)  

{  

int length = str.length();  

for (int i = 0; i < length / 2; i++)  

 if (toupper(str[i]) != toupper(str[length - 1 - i]))

  return false;  

return true;  

}

int main()

{

array<string, 6> tests = { "madam", "abba", "22", "67876", "444244", "trymEuemYRT" };

for (auto test : tests) {

 cout << test << " is " << (isPalindrome(test) ? "" : "NOT ") << "a palindrome.\n";

}

}

Explanation:

The toupper() addition forces characters to uppercase, thereby making the comparison case insensitive.