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CSharp · Console

/Program.cs

using System;

public class Program
{
	public static void Main()
	{
		// split string 
		var hello = "Hello World";
		// splt using l as the search substring
		string[] words = hello.ToLower().Split("l");
		var resultString = "";
		
		for (int i = 0; i < words.Length; i++)
		{
			// now we have split the string how do find the missing 'l' and wrap a span around them
			resultString += words[i].ToString();
		}
		// result is heo word
		Console.WriteLine(resultString);
		// Trying to get the result to be "He<span>l</span><span>l</span>o Wor<span>l<span>d
	}
}