# “ClosureAndVariable” (Solution)

## Answer

```
2
```

## Explanation

The code is translated into the following form:

```csharp
class DisplayClass
{
  public string startLetter;

  public bool Method1(string c)
  {
    return c.StartsWith(this.startLetter);
  }

  public bool Method2(string c)
  {
    return c.StartsWith(this.startLetter);
  }
}

void Main()
{
  DisplayClass displayClass = new DisplayClass();
  var list1 = new List<string> { "Foo", "Bar", "Baz" };
  var list2 = list1;
  displayClass.startLetter = "F";
  IEnumerable<string> source = list2.Where(displayClass.Method1);
  displayClass.startLetter = "B";
  Console.WriteLine(source.Where(displayClass.Method2).Count());
}
```

The execution of the LINQ queries will start only in the last line of code. As can be seen, the same helper class creates for both queries. First, the `list2.Where(displayClass.Method1)` query will be executed. It returns `{ "Bar", "Baz" }` because `displayClass.startLetter` at the time of execution is `"B"`. Next, the `source.Where(displayClass.Method2)` query will be executed. It also returns `{ "Bar", "Baz" }`. The number of elements in the result is two.

[Problem](/problembookdotnet/en/linq/closureandvariable-p.md)


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://andreyakinshin.gitbook.io/problembookdotnet/en/linq/closureandvariable-s.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.