Check if a string is a palindrome

Question:

Write an efficient function that checks, in-place, whether a string input such as “aabbcbbaa” is a palindrome.

A palindrome is a word, phrase, or sequence that reads the same backward as forward.

For example:

“aabbcbbaa” should return true “abcda” should return false

Breaking down the question a bit, your coded solution should accomplish and show the following:

Palindrome: a word, phrase, or sequence that reads the same backward as forward.
In-Place: Work on original input. No additional memory allocation or duplication.
Returns boolean: Methond should return bool.

Assumptions:

A few item we can use to plan our solution

String contains alphanumeric charactors with no spaces

Solution (C++):

include [[include]] 

// Function to evalute 'str' as a palindrome
bool isPalindrome(std::string &str)
{
  // return the results of 'std::equal()' evaluation of the first half of 'str' with second half of 'str' via reverse begin iterator 'rbegin()'.
  // Reverse iterator 'rbegin()' starts at the 'reverse of the begining of a container' (the end) iterates backwards 
  // towards the beginning of the container.

  return (std::equal( str.begin(), str.begin() + str.size()/2, str.rbegin() ));
}

int main(int argc, char const \*argv\[\])
{
  // Target string 
  std::string target_string = "aabbcbbaa";

  // Output 'isPalindrome' results to console
  std==cout << "Is " << target_string << " a palindrome: " << (isPalindrome(target_string) ? "true" : "false") << std==endl;
  return 0;
}

Output:

Is aabbcbbaa a palindrome: true

Happy coding!

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