using System.Linq.Expressions;
public static void Main()
Console.WriteLine("Hello World");
BinaryExpression b1 = Expression.MakeBinary(ExpressionType.Add,
Expression.Constant(20));
BinaryExpression b2 = Expression.MakeBinary(ExpressionType.Add,
BinaryExpression b3 = Expression.MakeBinary(ExpressionType.Subtract,
int result = Expression.Lambda<Func<int>>(b3).Compile()();
Console.WriteLine(result);