using System;
using System.Text.RegularExpressions;
 
public class Test
{
	public static void Main()
	{
		string[] inputstrings = { "ComputerPart", "topaz", "questions" };//An array of input strings to manipulate.
        string output = "";
        Regex rgx = new Regex("t");//Regex pattern to match occurence of 't'.
        foreach (string inputstring in inputstrings)//Iterate through each string in collection.
        {
            output = rgx.Replace(inputstring, "success", int.MaxValue, 1);//Replace each occurence of 't' excluding those ocurring at position [0] in inputstring.
            Console.WriteLine(output);//Show output string.
        }
	}
}

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