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Javascript Algorithms #2: Palindromes

Philip Obosi on August 01, 2018

Palindromes! Palindromes!! Palindromes!!! Ooooh boy. I'm pretty sure that by now you are wondering what these are. You know personally as a softwa...
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Kushan Joshi • • Edited

Great explanation Justine, especially using the .each API. Since javascript is so versatile, I am adding one more solution which uses iterator from my previous article dev.to/kepta/how-i-learned-to-stop...

function isPalindrome(str) {
   const iter = [...str.toLowerCase()];
   for (let char of iter) {
      if (char !== iter.pop()) { return false}
   }
   return true
}

The good thing about this is that it iterates only over half of the string to check if it is palindrome.

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jean luc tuyishime •

Do you have an idea on how you can do permutation of palindrome??

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Saurabh Sharma •

those memories of solving algorithms at freecodecamp.org

const isPalindrome = str => str.toLowerCase() === str.toLowerCase().split().reverse().join()
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Mahmoud Aslan •

nice, somehow didn't work until i added the splitters for split() and join()

const isPalindrome = str => str.toLowerCase() === str.split('').reverse().join('')
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Saurabh Sharma •

thats why we needs unit tests 😅

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Philip Obosi • • Edited

Thanks for the save. I didn't even look at the syntax closely. It's still a pretty concise solution though

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Philip Obosi •

Clean and concise

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Steveen Echeverri •

Palindrome example for a word, phrase, number or sequence of characters:

const isPalindrome = str => [...`${str}`].reverse().join('') == str;
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Kenthmordecai •

Great!