<jupyter_start><jupyter_text>Lists of Other TypesWatch the full [C 101 video](https://www.youtube.com/watch?v=oIQdb93xewE&list=PLdo4fOcmZ0oVxKLQCHpiUWun7vlJJvUiN&index=14) for this module.You've been practicing lists of strings, but you can make a list of anything! Here's a number example. FibonacciFibonacci is a cool number sequence. It adds up the last two numbers up to make the next number. You start with 1 and 11 + 1 = 2  (1, 1, 2)1 + 2 = 3  (1, 1, 2, 3)2 + 3 = 5  (1, 1, 2, 3, 5)3 + 5 = 8  (1, 1, 2, 3, 5, 8)and so on. There are lots of stuff in nature that follow this number sequence, and has lots of cool stuff if you want to look it up!> Start with the base numbers: Here's a list with just 1, 1 in it. Run it and see what happens.<jupyter_code>var fibonacciNumbers = new List<int> {1, 1};

foreach (var item in fibonacciNumbers)
    Console.WriteLine(item);<jupyter_output>1
1<jupyter_text>Now, you don't want just 1,1 in it! You want more of the sequence. In this code, you're using the last two numbers of the list, adding them together to make the next number, then adding it to the list.> Run the code to try it out.<jupyter_code>var fibonacciNumbers = new List<int> {1, 1}; // Starting the list off with the basics

var previous = fibonacciNumbers[fibonacciNumbers.Count - 1]; // Take the last number in the list
var previous2 = fibonacciNumbers[fibonacciNumbers.Count - 2]; // Take the second to last number in the list

fibonacciNumbers.Add(previous + previous2); // Add the previous numbers together, and attach the sum to the end of the list

foreach (var item in fibonacciNumbers) // Print out the list
    Console.WriteLine(item);<jupyter_output>1
1
2<jupyter_text>Count -1Why do you need to do `fibonacciNumbers.Count -1` to get the last number of the list? Well, `Count` tells you how many items are in a list. However, the index of an item starts at zero. So, if you only had one item in your list, the count would be one, but the index of the item would be 0. The index and count of the last item is always one off.  Challenge: Fibonacci to 20th numberWe've given you a base of code that deals with Fibonacci. Can you make a list that has the first 20 fibonacci numbers?> Make and print a list that has the first 20 fibonacci numbers.<jupyter_code>Console.WriteLine("Challenge");<jupyter_output>Challenge
{'fraction_non_alphanumeric': 0.0761986301369863, 'fraction_numerical': 0.02910958904109589, 'mean_word_length': 4.275395033860045, 'pattern_counts': {'":': 0, '<': 12, '<?xml version=': 0, '>': 15, 'https://': 1, 'lorem ipsum': 0, 'www.': 1, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
{'chain_length': '3', 'dir': 'jupyter-structured-clean-dedup', 'id': '173887', 'license': 'MIT', 'n_tokens_mistral': 796, 'n_tokens_neox': 721, 'n_words': 361, 'path': 'csharp-101/12-Lists of Other Types.ipynb', 'repo_name': 'ScriptBox99/dotnet-csharp-notebooks', 'size': '2336'}