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.lang.reflect.Array;
import java.math.*;
import java.security.KeyStore.Entry;
import java.util.*;
 
public class Main {
	private InputStream is;
	private PrintWriter out;
	int time = 0, dp[][], DP[][], dist[], prime[], start[], parent[], end[],
			val[], black[], arr[], arr1[][];
	long MOD = (long) (1e9 + 9);
	ArrayList<Pair>[] amp;
	boolean b[], b1[];
	Pair prr1[];
	char ch[][], c[];
	HashSet<Integer> hs1 = new HashSet<>(), hs2 = new HashSet<>();
 
	public static void main(String[] args) throws Exception {
		new Thread(null, new Runnable() {
			public void run() {
				try {
 
					// new Main().soln();
				} catch (Exception e) {
					System.out.println(e);
				}
			}
		}, "1", 1 << 26).start();
		new Main().soln();
	}
 
	int MAX = 1000010, N, K, p = 1;
	PriorityQueue<Pair> pq;
	int Dp[][] = new int[1010][1010];
	int MOD1 = 1000000007, MOD2 = 1000000009;
	void solve() {
		int n = ni(), a = ni(), b = ni();
		int arr[] = na(n);
		int c = 0;
		int cnt= 0 ;
		for(int i = 0; i < n; i++){
			if(arr[i]==1){
				if(a>0){
					a--;
				}
				else if(b>0){
					b--;
					c++;
				}
				else if(c>0){
					c--;
				}
				else{
					cnt++;
				}
			}
			else{
				if(b>0){
					b--;
				}
				else{
					cnt+=2;
				}
			}
		}
		System.out.println(cnt);
	}
	class cell implements Comparable<cell>{
		char ch;
		int i;
		cell(char c, int x){
			ch = c;
			i = x;
		}
		public boolean equals(Object o) {
			cell other = (cell) o;
			return ((ch == other.ch && i == other.i));// || (v == other.u && u ==
			// other.v));
		}
		@Override
		public int compareTo(cell c) {
			if(this.ch<c.ch) return -1;
			if(this.ch==c.ch) {
				if(this.i<c.i)return 1;
				if(this.i==c.i) return 0;
				return -1;
			}
			return 1;
		}
 
		public String toString() {
			return "[u=" + ch + ", v=" + i + "]";
		}
		
	}
	int T[] = new int[100010], L[] = new int[100010];
	int P[][] = new int[100010][30];
 
	void process3(int N) {
		int i, j;
 
		// we initialize every element in P with -1
		for (i = 0; i < N; i++)
			for (j = 0; 1 << j < N; j++)
				P[start[i]][j] = -1;
 
		// the first ancestor of every node i is T[i]
		for (i = 0; i < N; i++)
			P[start[i]][0] = T[i];
 
		// bottom up dynamic programing
		for (j = 1; 1 << j < N; j++)
			for (i = 0; i < N; i++)
				if (P[start[i]][j - 1] != -1)
					P[start[i]][j] = P[P[start[i]][j - 1]][j - 1];
	}
 
	int query(int p, int q) {
		int tmp = 0, log = 0, i = 0;
 
		// if p is situated on a higher level than q then we swap them
		if (L[p] < L[q])
			tmp = p;
		p = q;
		q = tmp;
 
		// we compute the value of [log(L[p)]
		for (log = 1; 1 << log <= L[p]; log++)
			;
		log--;
 
		// we find the ancestor of node p situated on the same level
		// with q using the values in P
		for (i = log; i >= 0; i--)
			if (L[p] - (1 << i) >= L[q])
				p = P[p][i];
 
		if (p == q)
			return p;
 
		// we compute LCA(p, q) using the values in P
		for (i = log; i >= 0; i--)
			if (P[p][i] != -1 && P[p][i] != P[q][i])
				p = P[p][i];
		q = P[q][i];
 
		return T[p];
	}
 
	void dfs(int x) {
		b[x] = true;
		start[x] = time++;
		for (Pair p : amp[x]) {
			int u = p.u;
			if (!b[u]) {
				L[u] = L[x] + 1;
				dfs(u);
			}
		}
		end[x] = time;
	}
 
	long ans = 0;
 
	void recur(int i, int k, long sum) {
		if (k > K)
			return;
		if (k == K) {
			ans = Math.max(ans, sum);
		}
		for (int j = i; j < N; j++) {
 
			recur(j + 1, k + 1, sum);
		}
	}
 
	long[] mul(long arr[][], long temp[]) {
		long ans[] = new long[temp.length];
		for (int i = 0; i < arr.length; i++) {
			long sum = 0;
			for (int j = 0; j < arr.length; j++) {
				sum = (sum + arr[i][j] * temp[j]) % MOD;
			}
			ans[i] = sum;
		}
		return ans;
	}
 
	void printMat(long arr[][]) {
		for (int i = 0; i < arr.length; i++) {
			for (int j = 0; j < arr.length; j++) {
				System.out.print(arr[i][j] + " ");
			}
			System.out.println();
		}
		System.out.println("-----");
	}
 
	void printMat(long arr[]) {
		for (int i = 0; i < arr.length; i++) {
			System.out.print(arr[i] + " ");
		}
		System.out.println();
		System.out.println("-----");
	}
 
	long[][] matMul(int n, long arr[][], long y) {
		long iden[][] = new long[n][n];
		for (int i = 0; i < n; i++)
			iden[i][i] = 1;
		// printMat(iden);
		while (y > 0) {
			if (y % 2 == 1) {
				iden = mul(n, iden, arr);
				// printMat(iden);
				y--;
			} else {
				arr = mul(n, arr, arr);
				// printMat(arr);
				y /= 2;
			}
		}
		return iden;
	}
 
	long[][] mul(int n, long a1[][], long a2[][]) {
		long temp[][] = new long[n][n];
		for (int i = 0; i < n; i++) {
			for (int j = 0; j < n; j++) {
				long sum = 0;
				for (int k = 0; k < n; k++) {
					sum = (sum + a1[i][k] * a2[k][j]) % MOD;
				}
				temp[i][j] = sum;
			}
		}
		return temp;
	}
 
	void seive(int n) {
		b = new boolean[n + 1];
		prime = new int[n + 1];
		for (int i = 2; i * i <= n; i++) {
			if (!b[i]) {
				for (int j = 2 * i; j <= n; j += i) {
					if (!b[j]) {
						b[j] = true;
						prime[j] = i;
					}
				}
			}
		}
	}
 
	int binarySearch1(int arr[], int x) {
		int ans = -1;
		int low = 0, high = arr.length - 1;
		while (high >= low) {
			int mid = (low + high) / 2;
			if (arr[mid] >= x) {
				ans = mid;
				high = mid - 1;
			} else
				low = mid + 1;
		}
		return ans;
	}
 
	int binarySearch2(Integer arr[], int x) {
		int ans = -1;
		int low = 0, high = arr.length - 1;
		while (high >= low) {
			int mid = (low + high) / 2;
			if (arr[mid] >= x) {
				ans = mid;
				low = mid + 1;
			} else
				high = mid - 1;
		}
		return ans + 1;
	}
 
	int cntEven(String str) {
		int cnt = 0;
		for (int i = str.length() - 1; i >= 0; i--) {
			if ((str.charAt(i) - '0') % 2 == 0) {
				cnt++;
			}
		}
		return cnt;
	}
 
	int max = 0;
 
	int getParent(int x) {
		// System.out.println(x+" "+parent[x]);
		if (parent[x] != x) {
			parent[x] = getParent(parent[x]);
		}
		return parent[x];
	}
 
	class Pair implements Comparable<Pair> {
		int u;
		int v, r, i;
 
		Pair(int u, int v, int r, int i) {
			this.u = u;
			this.v = v;
			this.r = r;
			this.i = i;
		}
 
		Pair(int u, int v, int r) {
			this.u = u;
			this.v = v;
			this.r = r;
		}
 
		Pair(int u, int v) {
			this.u = u;
			this.v = v;
		}
 
		public int hashCode() {
			return Objects.hash();
		}
 
		public boolean equals(Object o) {
			Pair other = (Pair) o;
			return ((u == other.u && v == other.v));// || (v == other.u && u ==
			// other.v));
		}
 
		public int compareTo(Pair other) {
			//return Long.compare(r, other.r);
			 return Long.compare(u, other.u) != 0 ? (Long.compare(u, other.u))
			 : (Long.compare(v, other.v));
			// :(Long.compare(other.r, r))) ;
		}
 
	}
 
	int min(int x, int y) {
		if (x < y)
			return x;
		return y;
	}
 
	int max(int x, int y) {
		if (x > y)
			return x;
		return y;
	}
 
	void buildGraph(int m) {
		while (m-- > 0) {
			int x = ni() - 1, y = ni() - 1, r = ni();
			amp[x].add(new Pair(y, r));
			amp[y].add(new Pair(x, r));
			prr1[m] = new Pair(x, y, r);
		}
	}
 
	long modInverse(long a, long mOD2) {
		return power(a, mOD2 - 2, mOD2);
	}
 
	long power(long x, long y, long m) {
		if (y == 0)
			return 1;
		long p = power(x, y / 2, m) % m;
		p = (p * p) % m;
 
		return (y % 2 == 0) ? p : (x * p) % m;
	}
 
	boolean isPrime(int x) {
		for (int i = 2; i * 1L * i <= x; i++)
			if (x % i == 0)
				return false;
		return true;
	}
 
	public long gcd(long a, long b) {
		if (b == 0)
			return a;
		return gcd(b, a % b);
	}
 
	void failFn(String str, int arr[]) {
		int len = 0;
		arr[0] = 0;
		int i = 1;
		while (i < arr.length) {
			if (str.charAt(i) == str.charAt(len)) {
				arr[i++] = ++len;
				continue;
			}
			if (len == 0) {
				arr[i] = len;
				i++;
				continue;
			}
			if (str.charAt(i) != str.charAt(len)) {
				len = arr[len - 1];
			}
		}
	}
 
	static class ST1 {
		int arr[], st[], size;
 
		ST1(int a[]) {
			arr = a.clone();
			size = 10 * arr.length;
			st = new int[size];
			build(0, arr.length - 1, 1);
		}
 
		void build(int ss, int se, int si) {
			if (ss == se) {
				st[si] = arr[ss];
				return;
			}
			int mid = (ss + se) / 2;
			int val = 2 * si;
			build(ss, mid, val);
			build(mid + 1, se, val + 1);
			st[si] = (st[val] + st[val + 1]);
		}
 
		int get(int ss, int se, int l, int r, int si) {
			if (l > se || r < ss || l > r)
				return Integer.MAX_VALUE;
			if (l <= ss && r >= se)
				return st[si];
			int mid = (ss + se) / 2;
			int val = 2 * si;
			return (get(ss, mid, l, r, val) + get(mid + 1, se, l, r, val + 1));
		}
	}
 
	static class ST {
		int arr[], lazy[], n;
 
		ST(int a) {
			n = a;
			arr = new int[10 * n];
			lazy = new int[10 * n];
		}
 
		void up(int l, int r, int val) {
			update(0, n - 1, 0, l, r, val);
		}
 
		void update(int l, int r, int c, int x, int y, int val) {
			if (lazy[c] != 0) {
				lazy[2 * c + 1] ^= lazy[c];
				lazy[2 * c + 2] ^= lazy[c];
				if (l == r)
					arr[c] ^= lazy[c];
				lazy[c] = 0;
			}
			if (l > r || x > y || l > y || x > r)
				return;
			if (x <= l && y >= r) {
				if ((r - l + 1) % 2 == 1)
					lazy[c] ^= val;
				return;
			}
			int mid = l + r >> 1;
		update(l, mid, 2 * c + 1, x, y, val);
		update(mid + 1, r, 2 * c + 2, x, y, val);
		arr[c] = (arr[2 * c + 1] + arr[2 * c + 2]);
		}
 
		int an(int ind) {
			return ans(0, n - 1, 0, ind);
		}
 
		int ans(int l, int r, int c, int ind) {
			if (lazy[c] != 0) {
				lazy[2 * c + 1] += lazy[c];
				lazy[2 * c + 2] += lazy[c];
				if (l == r)
					arr[c] += lazy[c];
				lazy[c] = 0;
			}
			if (l == r)
				return arr[c];
			int mid = l + r >> 1;
		if (mid >= ind)
			return ans(l, mid, 2 * c + 1, ind);
		return ans(mid + 1, r, 2 * c + 2, ind);
		}
	}
	static long[] array;
	public static class FenwickTree {
 
		 // 1-indexed array, In this array We save cumulative
		// information to perform efficient range queries and
		// updates
 
		public FenwickTree(int size) {
			array = new long[size + 1];
		}
		int getSum(int index)
		{
			int sum = 0; // Iniialize result
 
			// index in BITree[] is 1 more than the index in arr[]
			index = index + 1;
 
			// Traverse ancestors of BITree[index]
			while (index>0)
			{
				// Add current element of BITree to sum
				sum ^= array[index];
 
				// Move index to parent node in getSum View
				index -= index & (-index);
			}
			return sum;
		}
		public long rsq(int ind) {
			assert ind > 0;
			long sum = 0;
			ind = ind+1;
			while (ind > 0) {
				sum ^= array[ind];
				// Extracting the portion up to the first significant one of the
				// binary representation of 'ind' and decrementing ind by that
				// number
				ind -= ind & (-ind);
			}
			return sum;
		}
 
		public long rsq(int a, int b) {
			assert b >= a && a > 0 && b > 0;
			return rsq(b) ^ rsq(a - 1);
		}
 
		public void update(int ind, long value) {
			assert ind > 0;
			ind = ind+1;
			while (ind < array.length) {
				array[ind] ^= value;
				// Extracting the portion up to the first significant one of the
				// binary representation of 'ind' and incrementing ind by that
				// number
				ind += ind & (-ind);
			}
		}
 
		public int size() {
			return array.length - 1;
		}
	}
 
	public static int[] shuffle(int[] a, Random gen) {
		for (int i = 0, n = a.length; i < n; i++) {
			int ind = gen.nextInt(n - i) + i;
			int d = a[i];
			a[i] = a[ind];
			a[ind] = d;
		}
		return a;
	}
 
	long power(long x, long y, int mod) {
		long ans = 1;
		while (y > 0) {
			if (y % 2 == 0) {
				x = (x * x) % mod;
				y /= 2;
			} else {
				ans = (x * ans) % mod;
				y--;
			}
		}
		return ans;
	}
 
	void soln() {
		is = System.in;
		out = new PrintWriter(System.out);
		long s = System.currentTimeMillis();
		solve();
		out.close();
		out.flush();
		tr(System.currentTimeMillis() - s + "ms");
	}
 
	// To Get Input
	// Some Buffer Methods
	private byte[] inbuf = new byte[1024];
	public int lenbuf = 0, ptrbuf = 0;
 
	private int readByte() {
		if (lenbuf == -1)
			throw new InputMismatchException();
		if (ptrbuf >= lenbuf) {
			ptrbuf = 0;
			try {
				lenbuf = is.read(inbuf);
			} catch (IOException e) {
				throw new InputMismatchException();
			}
			if (lenbuf <= 0)
				return -1;
		}
		return inbuf[ptrbuf++];
	}
 
	private boolean isSpaceChar(int c) {
		return !(c >= 33 && c <= 126);
	}
 
	private int skip() {
		int b;
		while ((b = readByte()) != -1 && isSpaceChar(b))
			;
		return b;
	}
 
	private double nd() {
		return Double.parseDouble(ns());
	}
 
	private char nc() {
		return (char) skip();
	}
 
	private String ns() {
		int b = skip();
		StringBuilder sb = new StringBuilder();
		while (!(isSpaceChar(b))) { // when nextLine, (isSpaceChar(b) && b != '
			// ')
			sb.appendCodePoint(b);
			b = readByte();
		}
		return sb.toString();
	}
 
	private char[] ns(int n) {
		char[] buf = new char[n];
		int b = skip(), p = 0;
		while (p < n && !(isSpaceChar(b))) {
			buf[p++] = (char) b;
			b = readByte();
		}
		return n == p ? buf : Arrays.copyOf(buf, p);
	}
 
	private char[][] nm(int n, int m) {
		char[][] map = new char[n][];
		for (int i = 0; i < n; i++)
			map[i] = ns(m);
		return map;
	}
 
	private int[] na(int n) {
		int[] a = new int[n];
		for (int i = 0; i < n; i++)
			a[i] = ni();
		return a;
	}
 
	private int ni() {
		int num = 0, b;
		boolean minus = false;
		while ((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'))
			;
		if (b == '-') {
			minus = true;
			b = readByte();
		}
 
		while (true) {
			if (b >= '0' && b <= '9') {
				num = num * 10 + (b - '0');
			} else {
				return minus ? -num : num;
			}
			b = readByte();
		}
	}
 
	private long nl() {
		long num = 0;
		int b;
		boolean minus = false;
		while ((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'))
			;
		if (b == '-') {
			minus = true;
			b = readByte();
		}
 
		while (true) {
			if (b >= '0' && b <= '9') {
				num = num * 10 + (b - '0');
			} else {
				return minus ? -num : num;
			}
			b = readByte();
		}
	}
 
	private boolean oj = System.getProperty("ONLINE_JUDGE") != null;
 
	private void tr(Object... o) {
		if (!oj)
			System.out.println(Arrays.deepToString(o));
	}
} 