Implement multiple files tests

Codeforces.Test/Input/2

@@ -0,0 +1,6 @@
+5
+256 42
+1000 1000
+-1000 1000
+-1000 1000
+20 22

Codeforces.Test/Output/2.a

@@ -0,0 +1,5 @@
+298
+2000
+0
+0
+42

Codeforces.Test/Tests.cs

@@ -1,17 +1,21 @@
+using System.Collections;
+
 namespace Codeforces.Test;
 
 public class Tests
 {
-	[Fact]
-	public void TestIO()
+
+	[Theory]
+	[ClassData(typeof(FileNameGenerator))]
+	public void TestIO(string input, string output)
 	{
 		IOTester.Start();
-		var lines = File.ReadLines(@"..\..\..\input.txt");
+		var lines = File.ReadLines(input);
 		IOTester.SetInput(lines.ToArray());
 
 		Program.Main();
 
-		string[] expectedOutput = File.ReadLines(@"..\..\..\output.txt").ToArray();
+		string[] expectedOutput = File.ReadLines(output).ToArray();
 		string[] actualOutput = IOTester.GetOutputLines();
 		Assert.Equal(expectedOutput.Length, actualOutput.Length);
 		for (int i = 0; i < expectedOutput.Length; i++)
@@ -19,4 +23,19 @@ public class Tests
 			Assert.Equal(expectedOutput[i], actualOutput[i]);
 		}
 	}
+}
+public class FileNameGenerator : IEnumerable<object[]>
+{
+	private readonly string inputFolder = @"..\..\..\Input";
+	public IEnumerator<object[]> GetEnumerator()
+	{		
+		foreach (var input in Directory.GetFiles(inputFolder))
+		{
+			string name = Path.GetFileName(input);
+			string output = $"..\\..\\..\\Output\\{name}.a";
+			yield return new object[] {input, output};
+		}
+	}
+
+	IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
 }