Input numbers only - Using Swift - Swift Forums
String Functions and Operators in Swift - GeeksforGeeks
JavaScript basic: Create a new string from a given string with the first character of the given string added at the front and back - w3resource
2 ways to find the first and last character of a string in Swift - CodeVsColor
swift - Can I filter the first character as String and second character as Int on an Array? - Stack Overflow
2 ways to find the first and last character of a string in Swift - CodeVsColor
Different ways to check if a string contains another string in Swift | Sarunw
How does String substring work in Swift - Stack Overflow
Swift String Programming Exercise: Accept two strings and return their concatenation, except the first char of each string - w3resource
Why can't Swift strings be subscripted with integers? - Quora
How to replace characters in string with Swift
Set character limit on UITextField and UITextView with Swift
Swift String – dropFirst()
Swift Basic Programming Exercise: Create a new string where all the character "a" have been removed except the first and last positions - w3resource
Remove the first six characters from a String (Swift) - Stack Overflow
Remove First Character From String in Swift - YouTube
2 ways to find the first and last character of a string in Swift - CodeVsColor
How to get the first character of a string in Swift / mrGURU - YouTube
How to uppercase first character in a Swift string | Xcode Tutorial - YouTube
ios - Swift - Remove white spaces from string doesn't work - Stack Overflow
