import Foundation
// By using a CharacterSet that includes everything except
// letters and numbers, we can naturally split the string while
// correctly identifying that 世界 is a word and 、 is a separator.
/**
* Returns the word before the last word.
* Uses Swift's native Unicode-aware CharacterSet to handle international scripts.
*/
func getWordBeforeLast(_ text: String) -> String {
// 1. Define a character set of everything we want to keep (Letters and Numbers).
// 2. Invert it to get a set of "separators" (punctuation, whitespace, etc.).
let separators = CharacterSet.letters.union(.decimalDigits).inverted
// 3. Split the string by those separators.
// omittingEmptySubsequences handles multiple spaces/punctuation automatically.
let words = text.components(separatedBy: separators)
.filter { !$0.isEmpty }
// Check if we have at least two words
guard words.count >= 2 else {
return "null"
}
// Return the second to last word
return words[words.count - 2]
}
func main() {
print("=== Testing: Get Word Before Last ===\n")
let tests = [
"python swift",
" many spaces here now ",
"OneWord",
"",
" ",
"Hello, world!",
"Tabs\tand\nnewlines work too",
"Unicode 世界、こんにちは",
"Ends with punctuation.",
"Multiple words, with punctuation, here!",
"state-of-the-art program example"
]
for t in tests {
let result = getWordBeforeLast(t)
print("Input: \"\(t)\"")
print("Output: \(result)")
print(String(repeating: "-", count: 40))
}
}
main()
/*
OUTPUT:
=== Testing: Get Word Before Last ===
Input: "python swift"
Output: python
----------------------------------------
Input: " many spaces here now "
Output: here
----------------------------------------
Input: "OneWord"
Output: null
----------------------------------------
Input: ""
Output: null
----------------------------------------
Input: " "
Output: null
----------------------------------------
Input: "Hello, world!"
Output: Hello
----------------------------------------
Input: "Tabs and
newlines work too"
Output: work
----------------------------------------
Input: "Unicode 世界、こんにちは"
Output: 世界
----------------------------------------
Input: "Ends with punctuation."
Output: with
----------------------------------------
Input: "Multiple words, with punctuation, here!"
Output: punctuation
----------------------------------------
Input: "state-of-the-art program example"
Output: program
----------------------------------------
*/
