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CSharp · Console

/Program.cs

using System;
					
public class Program
{
	public static void Main()
	{
		var telefone = "+55 81 2345678";
		Console.WriteLine(telefone); //+55 81 2345678		
		
		Console.WriteLine(telefone.Substring(telefone.Length -8)); //2345678
		
		Console.WriteLine(telefone.Remove(telefone.Length - 8)); //+55 81 
		
	}
}