ThreeEqualNumber

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Numerics;
using System.Text;
using System.Threading.Tasks;

namespace Test
{
    class ThreeEqualNumber
    {
        static void Main()
        {
            string a = Console.ReadLine();
            string b = Console.ReadLine();
            string c = Console.ReadLine();
            int maxLength = Math.Max(a.Length , Math.Max(b.Length , c.Length));
            bool areEqual = true;

            a = a.PadRight(maxLength , '0');
            b = b.PadRight(maxLength , '0');
            c = c.PadRight(maxLength , '0');

            for(int i = 0; i < maxLength; i++)
            {
                if(a[i]!= b[i] || b[i]!=c[i])
                {
                    areEqual = false;
                }
            }

            if(areEqual)
            {
                Console.WriteLine("yes");
            }
            else
            {
                Console.WriteLine("no");
            }
        }
    }
}