Simple task

Codeforces.Console/IOTester.cs

@@ -0,0 +1,54 @@
+namespace Codeforces
+{
+    public class IOTester
+	{
+		private static readonly TextReader originalStdIn = Console.In;
+		private static StringReader? stdIn;
+
+		private static readonly TextWriter originalStdOut = Console.Out;
+		private static StringWriter? stdOut;
+
+		public static void Start()
+		{
+			stdOut = new StringWriter();
+			Console.SetOut(stdOut);
+		}
+
+		public static void End()
+		{
+			stdOut = null;
+			stdIn = null;
+			Console.SetOut(originalStdOut);
+			Console.SetIn(originalStdIn);
+		}
+
+		public static void SetInput(params string[] lines)
+		{
+			string input = string.Join(Environment.NewLine, lines);
+			stdIn = new StringReader(input);
+			Console.SetIn(stdIn);
+		}
+
+		public static string GetOutput()
+		{
+			if (stdOut == null)
+			{
+				return "";
+			}
+			else
+			{
+				return stdOut.ToString();
+			}
+		}
+
+		public static string[] GetOutputLines()
+		{
+			return GetOutput().Split(Environment.NewLine);
+		}
+
+		public static IList<string> GetOutputLinesAsList()
+		{
+			return new List<string>(GetOutputLines());
+		}
+	}
+}

Codeforces.Console/Program.cs

@@ -1,2 +1,17 @@
-// See https://aka.ms/new-console-template for more information
-Console.WriteLine("Hello, World!");
+namespace Codeforces
+{
+	public class Program
+	{
+		public static void Main(string[] args)
+		{
+			int count = int.Parse(Console.ReadLine()!);
+			for (int i = 0; i < count; i++)			
+			{
+				var numbers = Console.ReadLine()!
+					.Split(' ')
+					.Select(x => int.Parse(x));
+				Console.WriteLine(numbers.Sum());
+			}
+		}
+	}
+}

Codeforces.Test/Tests.cs

@@ -0,0 +1,40 @@
+namespace Codeforces.Test;
+
+public class Tests
+{
+	[Fact]
+	public void TestIO()
+	{
+		IOTester.Start();
+		
+		string[] input = new string[]
+		{
+			"5",
+			"256 42",
+			"1000 1000",
+			"-1000 1000",
+			"-1000 1000",
+			"20 22"
+		};		
+		IOTester.SetInput(input);
+
+		Program.Main(new string[0]);
+
+		string[] output = new string[]		
+		{
+			"298",
+			"2000",
+			"0",
+			"0",
+			"42"
+		};
+		
+		string[] actualOutput = IOTester.GetOutputLines();
+		Assert.Equal(output.Length, actualOutput.Length - 1);
+		for (int i = 0; i< output.Length; i++)		
+		{
+			Assert.Equal(output[i], actualOutput[i]);			
+		}
+	}
+
+}

Codeforces.Test/UnitTest1.cs

@@ -1,10 +0,0 @@
-namespace Codeforces.Test;
-
-public class UnitTest1
-{
-    [Fact]
-    public void Test1()
-    {
-
-    }
-}

Codeforces.Test/Usings.cs

@@ -1 +1,2 @@
-global using Xunit;
+global using Xunit;
+global using Codeforces;