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.io.*;
import java.util.*;
import java.math.*;
import java.lang.*;
 
import static java.lang.Math.*;
 
public class Sol {
 
    static long mod = 1000000007;
    
    public static void main(String args[]) throws Exception {
        //Scanner in;
        InputReader in;
        PrintWriter w;
        boolean online = false;
        String fileName = "input";
 
        if (online) {
            //in=new Scanner(new File(fileName + ".in"));
            in = new InputReader(new FileInputStream(new File(fileName + ".in")));
            w = new PrintWriter(new FileWriter("out.txt"));
        } else {
            //in=new Scanner(System.in);
            in = new InputReader(System.in);
            w = new PrintWriter(System.out);
        }
 
        //int T = in.nextInt();
        //in.nextLine();
        int T = 1;
 
        for (int t = 1; t <= T; t++) {
            int n = in.nextInt();
            int a = in.nextInt();
            int b = in.nextInt();
            int B = 0;
            
            int sum = 0;
            
            for(int i=0;i<n;i++) {
                int x = in.nextInt();
                
                if(x == 1) {
                    if(a == 0) {
                        if(b != 0) {
                            B++;
                            b--;
                        }
                        else {
                            if(B != 0) {
                                B--;
                            }
                            else {
                                sum++;
                            }
                        }
                    }
                    else {
                        a--;
                    }
                }
                else {
                    if(b!=0) b--;
                    else {
                        sum+=2;
                    }
                }
            }
            
            w.println(sum);
        }
        
        w.close();
    }
    
    static class compare implements Comparator<pair>
    {
        @Override
        public int compare(pair p1, pair p2)
        {
            if(p1.d != p2.d) return (p1.d - p2.d);
            return p1.s - p2.s;
        }
    }
    
    static class pair implements Comparable<pair>
    {
        int d, t, s, ok;
        
        public pair(int d, int t, int s)
        {
            this.d = d;
            this.t = t;
            this.s = s;
            //ok = 1;
        }
        
        @Override
        public int compareTo(pair p)
        {
            if(this.s != p.s) return (this.s - p.s);
            if(this.d != p.d) return (this.d - p.d);
            return (this.t - p.t);
        }
        
        /*              // ************  Use only when HashMap / HashSet of pair is taken       ******************* ////////
        @Override
        public boolean equals(Object p) {
            if(p instanceof pair) {
                pair P = (pair)p;
                return this.s == P.s && this.d == P.d;
            }
            
            return false;
        }

        @Override
        public int hashCode() {
            int hash = 7;
            hash = 79 * hash + this.d;
            //hash = 79 * hash + this.t;
            hash = 79 * hash + this.s;
            return hash;
        }*/
    }
 
    static int arr[];
    static int size[];
 
    static void initialize(int n) {
        for (int i = 0; i <= n; i++) {
            arr[i] = i;
            size[i] = 1;
        }
    }
 
    static int root(int r) {
        while (arr[r] != r) {
            arr[r] = arr[arr[r]];
            r = arr[r];
        }
 
        return r;
    }
 
    static void union(int u, int v) {
        int r1 = root(u);
        int r2 = root(v);
 
        if (r1 != r2) {
            if (size[r1] < size[r2]) {
                arr[r1] = arr[r2];
                size[r2] += size[r1];
            } else {
                arr[r2] = arr[r1];
                size[r1] += size[r2];
            }
        }
    }
 
    private static long gcd(long a, long b) {
        while (b > 0) {
            long temp = b;
            b = a % b; // % is remainder
            a = temp;
        }
        return a;
    }
 
    private static long gcd(long[] input) {
        long result = input[0];
 
        for (int i = 1; i < input.length; i++) {
            result = gcd(result, input[i]);
        }
 
        return result;
    }
 
    private static long lcm(long a, long b) {
        return a * (b / gcd(a, b));
    }
 
    private static long lcm(long[] input) {
        long result = input[0];
 
        for (int i = 1; i < input.length; i++) {
            result = lcm(result, input[i]);
        }
 
        return result;
    }
 
    public static void Array_2dsort(Integer[][] a) {
        Arrays.sort(a, new Comparator<Integer[]>() {
            public int compare(Integer[] int1, Integer[] int2) {
                Integer numOfKeys1 = int1[1];       //about which column u want to sort
                Integer numOfKeys2 = int2[1];
                return numOfKeys1.compareTo(numOfKeys2);
            }
        });
    }
 
    static long powmod(long x, long n, long m) {
        if (n == 0) {
            return 1;
        } else if (n % 2 == 0) {
            return powmod(((x % m) * (x % m)) % m, n / 2, m);
        } else if (n % 2 == 1) {
            return (((x % m) * powmod(((x % m) * (x % m)) % m, (n - 1) / 2, m)) % m);
        } else {
            return 0;
        }
    }
 
    static class InputReader {
 
        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;
        private SpaceCharFilter filter;
 
        public InputReader(InputStream stream) {
            this.stream = stream;
        }
 
        public int read() {
            if (numChars == -1) {
                throw new InputMismatchException();
            }
 
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = stream.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
 
                if (numChars <= 0) {
                    return -1;
                }
            }
            return buf[curChar++];
        }
 
        public String nextLine() {
            BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
 
        public int nextInt() {
            int c = read();
 
            while (isSpaceChar(c)) {
                c = read();
            }
 
            int sgn = 1;
 
            if (c == '-') {
                sgn = -1;
                c = read();
            }
 
            int res = 0;
            do {
                if (c < '0' || c > '9') {
                    throw new InputMismatchException();
                }
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
 
            return res * sgn;
        }
 
        public long nextLong() {
            int c = read();
            while (isSpaceChar(c)) {
                c = read();
            }
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            long res = 0;
 
            do {
                if (c < '0' || c > '9') {
                    throw new InputMismatchException();
                }
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }
 
        public double nextDouble() {
            int c = read();
            while (isSpaceChar(c)) {
                c = read();
            }
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            double res = 0;
            while (!isSpaceChar(c) && c != '.') {
                if (c == 'e' || c == 'E') {
                    return res * Math.pow(10, nextInt());
                }
                if (c < '0' || c > '9') {
                    throw new InputMismatchException();
                }
                res *= 10;
                res += c - '0';
                c = read();
            }
            if (c == '.') {
                c = read();
                double m = 1;
                while (!isSpaceChar(c)) {
                    if (c == 'e' || c == 'E') {
                        return res * Math.pow(10, nextInt());
                    }
                    if (c < '0' || c > '9') {
                        throw new InputMismatchException();
                    }
                    m /= 10;
                    res += (c - '0') * m;
                    c = read();
                }
            }
            return res * sgn;
        }
 
        public String readString() {
            int c = read();
            while (isSpaceChar(c)) {
                c = read();
            }
            StringBuilder res = new StringBuilder();
            do {
                res.appendCodePoint(c);
                c = read();
            } while (!isSpaceChar(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;
        }
 
        public String next() {
            return readString();
        }
 
        public interface SpaceCharFilter {
 
            public boolean isSpaceChar(int ch);
        }
 
    }
 
}
 