Given string is Palindrome or not

Using whileAnother way

Code

func isPalindrome(_ string: String) -> Bool {
    let characters = Array(string.lowercased())
    var left = 0
    var right = characters.count - 1

    while left < right {
        if characters[left] != characters[right] {
            return false
        }
        left += 1
        right -= 1
    }

    return true
}

Example

// Example usage
print(isPalindrome("mom"))  // true
print(isPalindrome("Neveroddoreven"))  // true
print(isPalindrome("test"))  // false

Output

true
true
false

Code

func isPalindromeNew(_ input: String) -> Bool {
    let sanitizedInput = input.lowercased().replacingOccurrences(of: "[^a-z0-9]", with: "", options: .regularExpression)
    return sanitizedInput == String(sanitizedInput.reversed())
}

Example

print(isPalindromeNew("racecar"))  // true
print(isPalindromeNew("level"))    // true
print(isPalindromeNew("hello"))    // false
print(isPalindromeNew("A man, a plan, a canal: Panama")) // true

Output

true
true
false
true