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CSharp · Console

/Program.cs

using System;
using System.Text;	
public class Program
{
	public static void Main()
	{
		var line = "I like <CHOICE [cars and bikes] [apple and oranges]>";
		var result = new StringBuilder();
		var state = 0;

		foreach (char c in line)
		{
		   if (state == 0 && c == '<') state = 1;
		   else if (state == 1 && c == '[') state = 2;
		   else if (state == 2 && c == ']') state = 3;
		   else if (state == 3 && c == '>') state = 0;
		   else if (state == 0 || state == 2) result.Append(c);
		}
		Console.WriteLine(result);
	}
}