using System; using System.Collections.Generic; using System.Linq; using System.Numerics; using static System.Console; using static System.Math; class Program { static void Main() { var r =ReadLine(); var a=true; for (int i = 0; i < r.Length; i++) { if(i%2==1&&r[i]!=' ')a=false; } WriteLine(a?"Yes":"No"); } }