Problem:
Score : 200 points

Problem Statement

Snuke lives on an infinite two-dimensional plane. He is going on an N-day trip.
At the beginning of Day 1, he is at home. His plan is described in a string S of length N.
On Day i(1 ≦ i ≦ N), he will travel a positive distance in the following direction:

North if the i-th letter of S is N

West if the i-th letter of S is W

South if the i-th letter of S is S

East if the i-th letter of S is E

He has not decided each day's travel distance. Determine whether it is possible to set each day's travel distance so that he will be back at home at the end of Day N.

Constraints

1 ≦ | S | ≦ 1000

S consists of the letters N, W, S, E.

Input

The input is given from Standard Input in the following format:

S

Output

Print Yes if it is possible to set each day's travel distance so that he will be back at home at the end of Day N. Otherwise, print No.

Sample Input 1

SENW

Sample Output 1

Yes

If Snuke travels a distance of 1 on each day, he will be back at home at the end of day 4.

Sample Input 2

NSNNSNSN

Sample Output 2

Yes

Sample Input 3

NNEW

Sample Output 3

No

Sample Input 4

W

Sample Output 4

No

Solution in C# (Mono 4.6.2.0) (judge verdict: Accepted)

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

namespace SandboxCSharp
{
    class Solver
    {
        public void Solve()
        {
            string str = io.ScanString();
            int n = str.Length;
            int xok = 0, yok = 0;

            foreach (char c in str)
            {
                if (c == 'N')
                    yok |= 1;
                if (c == 'S')
                    yok |= 2;
                if (c == 'W')
                    xok |= 1;
                if (c == 'E')
                    xok |= 2;
            }
            if ((xok == 0 || xok == 3) && (yok == 0 || yok == 3))
                io.WriteLine("Yes");
            else
                io.WriteLine("No");
        }

        // =================================================
        // =================================================

        Stdio io;
        bool isjdg;
        static void Main()
        {
            var s = new Solver();
            s.Solve();
            s.io.Flush();
        }
        public Solver(Stdio _io = null)
        {
            isjdg = _io == null;
            io = _io == null ? new Stdio() : _io;
        }

        void Exit()
        {
            if (isjdg)
            {
                io.Flush();
                Environment.Exit(0);
            }
            else
                throw new HaltException();
        }
    }
    class Stdio
    {
        protected string[] stack = new string[0];
        protected int stackptr = 0;
        protected StringBuilder outbuff = new StringBuilder();

        public virtual int ScanInt()
        {
            return Check() ? int.Parse(stack[stackptr++]) : 0;
        }
        public virtual long ScanLong()
        {
            return Check() ? long.Parse(stack[stackptr++]) : 0;
        }
        public virtual string ScanString()
        {
            return Check() ? stack[stackptr++] : string.Empty;
        }
        public virtual double ScanDouble()
        {
            return Check() ? double.Parse(stack[stackptr++]) : 0;
        }
        protected virtual bool Check()
        {
            if (stackptr < stack.Length) return true;
            var l = Console.ReadLine();
            if (l == null) return false;
            stack = l.Split(' ').ToArray(); stackptr = 0;
            return Check();
        }
        public Stdio Write(long v) { return Write($"{v}"); }
        public Stdio WriteLine(long v) { return WriteLine($"{v}"); }
        public Stdio Write(string str)
        {
            outbuff.Append(str);
            return this;
        }
        public Stdio WriteLine(string str = "")
        {
            outbuff.AppendLine(str);
            return this;
        }
        public virtual Stdio Flush()
        {
            Console.Write(outbuff.ToString());
            outbuff.Clear();
            return this;
        }
    }
    class HaltException : Exception { }

}