Hey there! I see you're trying to pull number pairs from a string like "(1,1)(3,3)(4,4)" and turn them into a 2D array, but your current regex is including commas and not capturing the full pairs correctly. Let's fix that step by step.

What's Wrong with the Original Regex? #

Your pattern \d(,)\d only matches single digits around a comma, and it captures the comma as part of the match. It also doesn't account for multi-digit numbers (like (10,20)) or properly isolate each pair inside parentheses.

The Corrected Regex #

We need a pattern that targets each parenthesized pair and captures the two numbers separately:

\((\d+),(\d+)\)

Let's break this down:

• \(: Escapes the left parenthesis (since parentheses are special regex characters)
• (\d+): First capture group, matches one or more digits (supports multi-digit numbers)
• ,: Matches the comma separating the numbers
• (\d+): Second capture group, matches the second number
• \): Escapes the right parenthesis

Updated Swift Code #

Here's how to implement this to build your 2D array:

let str = "(1,1) (2,2) (3,3)"
let pattern = "\\((\\d+),(\\d+)\\)" // Double backslashes for Swift string escaping
let regex = try! NSRegularExpression(pattern: pattern)
let range = NSRange(str.startIndex..., in: str)

var numberPairs: [[Int]] = []

// Iterate through all matches and extract the captured numbers
regex.enumerateMatches(in: str, options: [], range: range) { match, _, _ in
    guard let match = match else { return }
    
    // Extract first number from capture group 1
    if let num1Range = Range(match.range(at: 1), in: str),
       let num1 = Int(str[num1Range]) {
        // Extract second number from capture group 2
        if let num2Range = Range(match.range(at: 2), in: str),
           let num2 = Int(str[num2Range]) {
            numberPairs.append([num1, num2])
        }
    }
}

print(numberPairs) // Output: [[1, 1], [2, 2], [3, 3]]

Key Improvements #

• Supports multi-digit numbers: Works with pairs like (123,456) instead of just single digits
• Captures pure numbers: No more dealing with commas—we directly grab the digits from the capture groups
• Handles any spacing: Works whether pairs are separated by spaces (like your example) or not (e.g., "(1,1)(3,3)(4,4)")

内容的提问来源于stack exchange，提问作者John Aron