List Type Safety

List<T> stores a collection where every item has the same type.

ListTypeSafety.cs

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        int extra = ;
        List<int> scores = new List<int>();
        scores.Add(10);
        scores.Add(extra);

        int total = 0;
        foreach (int score in scores)
        {
            total += score;
        }

        Console.WriteLine($"extra={extra}");
        Console.WriteLine($"count={scores.Count}");
        Console.WriteLine($"total={total}");
    }
}

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        int extra = ;
        List<int> scores = new List<int>();
        scores.Add(10);
        scores.Add(extra);

        int total = 0;
        foreach (int score in scores)
        {
            total += score;
        }

        Console.WriteLine($"extra={extra}");
        Console.WriteLine($"count={scores.Count}");
        Console.WriteLine($"total={total}");
    }
}

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        int extra = ;
        List<int> scores = new List<int>();
        scores.Add(10);
        scores.Add(extra);

        int total = 0;
        foreach (int score in scores)
        {
            total += score;
        }

        Console.WriteLine($"extra={extra}");
        Console.WriteLine($"count={scores.Count}");
        Console.WriteLine($"total={total}");
    }
}

type safety Type safety catches mismatched values before a program runs.