Script•3y ago

Script – 13-45 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?

11 Replies

Unknown User•3y ago

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Script•3y 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.

Unknown User•3y ago

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Script•3y ago

it would return -1

Unknown User•3y ago

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Script•3y ago

Unknown User•3y ago

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Script•3y ago

sorry 1

Unknown User•3y ago

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Script•3y ago

reactibot•3y ago

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