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CSharp · Console

/Program.cs

using System;
using System.Text.RegularExpressions;
					
public class Program
{
	private static string ConvertSuperscriptToText(Match m){
        string res = m.Groups[1].Value;
			
	    res = "^" + res;
        return res;
    }
	public static void Main()
	{
        string expression = "2⁻¹² + 3³ / 4⁽³⁻¹⁾";
        string desiredResult = "2^-12 + 3^3 / 4^(3-1)";
		
		string supChars = "([¹²³⁴⁵⁶⁷⁸⁹⁰⁺⁻⁽⁾]+)";
        string result = Regex.Replace(expression, supChars, ConvertSuperscriptToText);

		Console.WriteLine(result); // Currently prints 2^⁻¹² + 3^³ / 4^⁽³⁻¹⁾
        Console.WriteLine(result == desiredResult); // Currently prints false
	}
}