28. Find the Index of the First Occurrence in a String

Given two strings needle and haystack, return the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack. Leetcode Qn :

   
  
public class Solution {
    

 public int StrStr(string haystack, string needle) {
         string mainString = haystack;
        string searchString = needle;

        int indexOfFirstOccurrence = mainString.IndexOf(searchString);

        if (indexOfFirstOccurrence != -1)
        {
            Console.WriteLine($"The first occurrence of '{searchString}' is at index: {indexOfFirstOccurrence}");
            return  indexOfFirstOccurrence;
        }
        else
        {
            Console.WriteLine($"'{searchString}' not founds in the string.");
        }
        return  indexOfFirstOccurrence;
    }
        
}