Script•4y ago

Script – 19-47 Feb 2

I am trying to create a palindrome algorithm to make a word a palindrome and return the index I have to remove to make it a palindrome. I came up with this:

function palindromeIndex(s) {
  let re = /[\W_]/g;

  let lowRegStr = s.toLowerCase().replace(re, "").split("");
  let reverseStr = s.toLowerCase().replace(re, "").split("").reverse();
  let removed;
  let removedRev;

  if (lowRegStr.join("") === reverseStr.join("")) {
    return -1;
  }

  for (let i = 0, k = s.length - 1; i < s.length; i++, k--) {
    removed = lowRegStr.splice(i, 1);
    removedRev = reverseStr.splice(k, 1);

    if (lowRegStr.join("") === reverseStr.join("")) {
      return i;
    }
    lowRegStr.splice(i, 0, ...removed);
    reverseStr.splice(k, 0, ...removedRev);
  }

  return -1;
}
console.log(palindromeIndex("eye"));

function palindromeIndex(s) {
  let re = /[\W_]/g;

  let lowRegStr = s.toLowerCase().replace(re, "").split("");
  let reverseStr = s.toLowerCase().replace(re, "").split("").reverse();
  let removed;
  let removedRev;

  if (lowRegStr.join("") === reverseStr.join("")) {
    return -1;
  }

  for (let i = 0, k = s.length - 1; i < s.length; i++, k--) {
    removed = lowRegStr.splice(i, 1);
    removedRev = reverseStr.splice(k, 1);

    if (lowRegStr.join("") === reverseStr.join("")) {
      return i;
    }
    lowRegStr.splice(i, 0, ...removed);
    reverseStr.splice(k, 0, ...removedRev);
  }

  return -1;
}
console.log(palindromeIndex("eye"));

It works fine but after running tests I discovered its not efficient. What other efficient way can be used?

2 Replies

ScriptOP•4y ago

palindromeIndex("eye") Input is a string Expected output should be -1 because it's a palindrome already But if we have "eyes", expected output should be 3 which is the index of the letter needed to be removed to make it a palindrome Definition of palindrome : a word, verse, or sentence (such as "Able was I ere I saw Elba") or a number (such as 1881) that reads the same backward or forward.

reactibot•4y ago

This thread hasn’t had any activity in 12 hours, so it’s now locked. Threads are closed automatically after 12 hours. If you have a followup question, you may want to reply to this thread so other members know they're related. https://discord.com/channels/102860784329052160/565213527673929729/938521025778446427

Script – 19-47 Feb 2

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