how do you determine if a string is a palindrome in typescript

To check if a string is a palindrome in TypeScript, we can follow these steps:

1. Convert the string to an array of characters using the string split() method.
2. Create two pointers, one at the beginning of the array and another at the end.
3. Iterate through the array using a loop while the left pointer is less than the right pointer.
4. Check if the character at the left pointer equals the character at the right pointer using conditionals.
5. If the characters are not equal, the string is not a palindrome. Return false.
6. If the loop completes without finding any unequal characters, the string is a palindrome. Return true.

Here's the TypeScript code for this:

index.ts
function isPalindrome(str: string): boolean {
  const arr = str.split('');
  let left = 0;
  let right = arr.length - 1;
  
  while (left < right) {
    if (arr[left] !== arr[right]) {
      return false;
    }
    left++;
    right--;
  }
  
  return true;
}
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We first split the string into an array called arr. We then set two pointers, left and right, to the beginning and end of the array respectively.

Next, we use a while loop to iterate through the array as long as the left pointer is less than the right pointer. Within the loop, we use a conditional to check whether the character at the left pointer equals the character at the right pointer. If they are not equal, the function returns false because the string is not a palindrome.

Finally, if the loop completes without finding any unequal characters, the function returns true because the string is a palindrome.