Modify a letter in a string

Proposed exercise

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Create a function named "ChangeChar" to modify a letter in a certain position (0 based) of a string, replacing it with a different letter:

string sentence = "Tomato";

ChangeChar(ref sentence, 5, 'a');

Output

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Solution

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using System;
class ModifyLetter
{
    public static void ChangeChar(ref string text, int position, char letter) 
    {
        text = text.Remove(position, 1);
        text = text.Insert(position, letter.ToString());
    }

    public static void Main()
    {
        string sentence = "Tomato";
        ChangeChar(ref sentence, 5, 'a');
    }
}