In a small restaurant there are a tables for one person and b tables for two persons. 

It it known that n groups of people come today, each consisting of one or two people. 

If a group consist of one person, it is seated at a vacant one-seater table. If there are none of them, it is seated at a vacant two-seater table. If there are none of them, it is seated at a two-seater table occupied by single person. If there are still none of them, the restaurant denies service to this group.

If a group consist of two people, it is seated at a vacant two-seater table. If there are none of them, the restaurant denies service to this group.

You are given a chronological order of groups coming. You are to determine the total number of people the restaurant denies service to.

Input

The first line contains three integers n, a and b (1 ≤ n ≤ 2·105, 1 ≤ a, b ≤ 2·105) — the number of groups coming to the restaurant, the number of one-seater and the number of two-seater tables.

The second line contains a sequence of integers t1, t2, ..., tn (1 ≤ ti ≤ 2) — the description of clients in chronological order. If ti is equal to one, then the i-th group consists of one person, otherwise the i-th group consists of two people.

Output

Print the total number of people the restaurant denies service to.

Examples

Input

4 1 2
1 2 1 1


Output

0


Input

4 1 1
1 1 2 1


Output

2

Note

In the first example the first group consists of one person, it is seated at a vacant one-seater table. The next group occupies a whole two-seater table. The third group consists of one person, it occupies one place at the remaining two-seater table. The fourth group consists of one person, he is seated at the remaining seat at the two-seater table. Thus, all clients are served.

In the second example the first group consists of one person, it is seated at the vacant one-seater table. The next group consists of one person, it occupies one place at the two-seater table. It's impossible to seat the next group of two people, so the restaurant denies service to them. The fourth group consists of one person, he is seated at the remaining seat at the two-seater table. Thus, the restaurant denies service to 2 clients. 
import java.util.*;
import java.io.*;
public class Main {
 
	static ArrayList<Integer> adj[];
	static char color[];
	static boolean b[],visited[],possible;
	static Map<Integer,HashSet<Integer>> s;
	static int totalnodes,colored;
	static int count[];
	static long sum[];
	public static void main(String[] args) throws IOException {
		
		
		in=new InputReader(System.in);
		w=new PrintWriter(System.out);
	   int n=in.nextInt(),a=in.nextInt(),b=in.nextInt();
	   int o=0;
	   int t=0;
	   int ans=0;
	   for(int i=0;i<n;i++)
	   {
		   int m=in.nextInt();
		   if(m==1 && a>0)
			   a--;
		   else if(m==1 && a<=0)
		   {
			   if(b>0)
				   {
				   b--;
				   o++;
				   }
			   else if(o>0)
				   o--;
			   else
				   ans++;
		   }
		   else if(m==2 && b>0)
			   b--;
		   else if(m==2 && b<=0)
			   ans=ans+2;
			   
	   }
System.out.println(ans);
	  // System.out.println(o+" "+t);
	 
	   
       w.close();			
		}
	public static String[] subString(String s, int n) 
	{
	    String[] st =new String[(n*n+n)/2];
	    for(int i=0;i<st.length;i++)
	    	st[i]="";
	    int l=0;
	    for (int len = 1; len <= n; len++) 
	    {    
	        // Pick ending point
	        for (int i = 0; i <= n - len; i++) 
	        {
	            //  Print characters from current
	            // starting point to current ending
	            // point.  
	            int j = i + len - 1;            
	            for (int k = i; k <= j; k++) 
	                st[l]+=s.charAt(k);
	      //w.println(st[l]);
	            l++;
	            //cout << endl;
	        }
	    }
	    return st;
	}
	  public static long factorial(long n)
	    {
	        long res = 1, i;
	        for (i=2; i<=n; i++)
	            res *= i;
	        return res;
	    }
	
   
	public static int factors(int n,int start){
		int count = 0;
		int i;
		for(i=1;i*i<n;i++)
			if(n%i == 0){
				if(i>start)	count++;
				if(n/i > start)	count++;
			}
		if(i*i == n && i>start)	count++;
		return count;
	}


 	public static int isPrime(int n){
	    int i;

	    if (n==2)
	        return 1;

	    if (n%2==0)
	        return 0;

	    for (i=3;i<=Math.sqrt(n);i+=2)
	        if (n%i==0)
	            return 0;

	    return 1;
	}

	
	static InputReader in;
	static PrintWriter w;
	public static void seive(long n){
		b = new boolean[(int) (n+1)];
	Arrays.fill(b, true);
		for(int i = 2;i*i<=n;i++){
			if(b[i]){
				sum[i]=count[i];
			//	System.out.println(sum[i]+" wf");
				for(int p = 2*i;p<=n;p+=i){
					b[p] = false;
					sum[i]+=count[p];  
					//System.out.println(sum[i]);
				}
			}
		
		}
	}
	static class Pair implements Comparable<Pair> {
		char c;
		int count;
		public Pair(){
			
		}
		public Pair(char u, int v) {
			this.c = u;
			this.count= v;
			
		}
		public int compareTo(Pair other) {
			
				return 0;
		}
		
		/*public String toString() {
			return "[u=" + u + ", v=" + v + "]";
		}*/
	}
	static class Node2{
		Node2 left = null;
		Node2 right = null;
		Node2 parent = null;
		int data;
	}
	
	//binaryStree
	static class BinarySearchTree{
		Node2 root = null;
		int height = 0;
		int max = 0;
		int cnt = 1;
		ArrayList<Integer> parent = new ArrayList<Integer>();
		HashMap<Integer, Integer> hm = new HashMap<Integer, Integer>();
		public void insert(int x){
			Node2 n = new Node2();
			n.data = x;
			if(root==null){
				root = n;
			}
			else{
				Node2 temp = root,temp2 = null;
				while(temp!=null){
					temp2 = temp;
					if(x>temp.data) temp = temp.right;
					else temp = temp.left;
				}
				if(x>temp2.data) temp2.right = n;
				else temp2.left = n;
				n.parent = temp2;
				parent.add(temp2.data);
			}
		}
		public Node2 getSomething(int x, int y, Node2 n){
			if(n.data==x || n.data==y) return n;
			else if(n.data>x && n.data<y) return n;
			else if(n.data<x && n.data<y) return getSomething(x,y,n.right);
			else return getSomething(x,y,n.left);
		}
		public Node2 search(int x,Node2 n){
			if(x==n.data){
				max = Math.max(max, n.data);
				return n;
			}
			if(x>n.data){
				max = Math.max(max, n.data);
				return search(x,n.right);
			}
			else{
				max = Math.max(max, n.data);
				return search(x,n.left);
			}
		}
		public int getHeight(Node2 n){
			if(n==null) return 0;
			height = 1+ Math.max(getHeight(n.left), getHeight(n.right));
			return height;
		}
	}
public static void debug(Object... o) {
	System.out.println(Arrays.deepToString(o));
}
 
public static String rev(String s)
{
	StringBuilder sb=new StringBuilder(s);
	sb.reverse();
	return sb.toString();
}
 
static long lcm(long a, long b)
{
    return a * (b / gcd(a, b));
}
 
static long gcd(long a, long b)
{
    while (b > 0)
    {
        long temp = b;
        b = a % b; // % is remainder
        a = temp;
    }
    return a;
}
 
public static long max(long x, long y, long z){
		if(x>=y && x>=z) return x;
		if(y>=x && y>=z) return y;
		return z;
	}
	static int[] sieve(int n,int[] arr)
	{
	for(int i=2;i*i<=n;i++)
	{
		if(arr[i]==0)
		{
			for(int j=i*2;j<=n;j+=i)
				arr[j]=1;
		}
	}
	return arr;
	}
 
 
 
 
static class InputReader {
 
private final InputStream stream;
private final byte[] buf = new byte[8192];
private int curChar, snumChars;
private SpaceCharFilter filter;
 
public InputReader(InputStream stream) {
  this.stream = stream;
}
 
public int snext() {
  if (snumChars == -1)
    throw new InputMismatchException();
  if (curChar >= snumChars) {
    curChar = 0;
    try {
      snumChars = stream.read(buf);
    } catch (IOException e) {
      throw new InputMismatchException();
    }
    if (snumChars <= 0)
      return -1;
  }
  return buf[curChar++];
}
 
public int nextInt() {
  int c = snext();
  while (isSpaceChar(c)) {
    c = snext();
  }
  int sgn = 1;
  if (c == '-') {
    sgn = -1;
    c = snext();
  }
  int res = 0;
  do {
    if (c < '0' || c > '9')
      throw new InputMismatchException();
    res *= 10;
    res += c - '0';
    c = snext();
  } while (!isSpaceChar(c));
  return res * sgn;
}
 
public long nextLong() {
  int c = snext();
  while (isSpaceChar(c)) {
    c = snext();
  }
  int sgn = 1;
  if (c == '-') {
    sgn = -1;
    c = snext();
  }
  long res = 0;
  do {
    if (c < '0' || c > '9')
      throw new InputMismatchException();
    res *= 10;
    res += c - '0';
    c = snext();
  } while (!isSpaceChar(c));
  return res * sgn;
}
 
public int[] nextIntArray(int n) {
	 return nextIntArray(n, 0);
	    }
	    
public int[] nextIntArray(int n, int off) {
	 int[] arr = new int[n + off];
	   for (int i = 0; i < n; i++) {
	    arr[i + off] = nextInt();
	    }
	    return arr;
	    }
	    
public long[] nextLongArray(int n) {
return nextLongArray(n, 0);
	    }
        
	public long[] nextLongArray(int n, int off) {
	 long[] arr = new long[n + off];
	 for (int i = 0; i < n; i++) {
		  arr[i + off] = nextLong();
		 }
 return arr;
	}
 
 
public String readString() {
  int c = snext();
  while (isSpaceChar(c)) {
    c = snext();
  }
  StringBuilder res = new StringBuilder();
  do {
    res.appendCodePoint(c);
    c = snext();
  } while (!isSpaceChar(c));
  return res.toString();
}
 
public String nextLine() {
  int c = snext();
  while (isSpaceChar(c))
    c = snext();
  StringBuilder res = new StringBuilder();
  do {
    res.appendCodePoint(c);
    c = snext();
  } while (!isEndOfLine(c));
  return res.toString();
}
 
public boolean isSpaceChar(int c) {
  if (filter != null)
    return filter.isSpaceChar(c);
  return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
}
 
private boolean isEndOfLine(int c) {
  return c == '\n' || c == '\r' || c == -1;
}
 
public interface SpaceCharFilter {
  public boolean isSpaceChar(int ch);
}
}
	
}