One day Bob is playing Zombie World video game. In Zombie World game each round will contain N zombie’s and each zombie’s energy is Zi (where 1<=i<=N). Bob will start the round with B energy. In order to move to the next level Bob need to kill all the N zombie's but Bob can select any one among N Zombie's. If energy of Bob (B) is less than Zombie energy (Zi) then Bob will die and lose the round else Bob will won, during the fighting with zombie, Bob will lose his energy by (Zi%2)+(Zi/2). At any point of game Bob will play optimally. Now your task is to find out whether Bob can reach to the next level or not.

Constraints:

//program
import java.io.*;

public class Zombie_World
{

public static void main(String args[])
{
try
{
int NumberOfZombies;
int zEnergies[];
String energies,result[], en[],EnergiesOfZombie;
boolean flag=true;
double BobEnergy,res;

BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

energies=br.readLine();
result=energies.split(” “);
BobEnergy=Double.parseDouble(result[0]);
NumberOfZombies=Integer.parseInt(result[1]);

zEnergies=new int[NumberOfZombies];

EnergiesOfZombie=br.readLine();
en=EnergiesOfZombie.split(” “);

for(int i=0;i<NumberOfZombies;i++)
{
zEnergies[i]=Integer.parseInt(en[i]);
res=(zEnergies[i]%2)+(zEnergies[i]/2);
BobEnergy=BobEnergy-res;
if(BobEnergy<0)
{
flag=false;break;
}
}

if(flag)System.out.print(“YES”);
else System.out.print(“NO”);

}

catch(NumberFormatException e)
{
System.out.print(“Invalid Input”);
}

catch(Exception e)
{
System.out.print(“Error”);
}
}
}