using static System.Console;
 
public class Test {
	public static void Main() {
		Teste teste = new Teste();
		//teste.array = new int[5];
		teste.array[0] = 1;
		teste.Array = new int[5];
		WriteLine(teste.Array.Length);
		teste.Array = new int[4];
		WriteLine(teste.Array.Length);
	}
}
 
public class Teste {
	public readonly int[] array = new int[4];
	private int[] array2 = new int[4];
	public int[] Array { get => array2;	set {
			if (value.Length == 4) array2 = value;
			//decide se quer gerar uma exceção no else
		}
	}
}
 
//https://pt.stackoverflow.com/q/570019/101

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