Codeforces828 A. Restaurant Tables

A. Restaurant Tables

time limit per test

1 second

memory limit per test

256 megabytes

input

standard input

output

standard output

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.

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题目的意思是有2人的位置和1人的位置，每次有一个或两个顾客过来，一个人的优先坐1人位置，再一个人空的坐2人位置，再做有一个人坐的2人位置，没有就走，两个人的只做空的2人位置，否则就走，先给出2种位置个数，求有多少人没被服务到

思路： 直接模拟记录位置的个数

 

#include <iostream>
#include <cstdio>
#include <cstring>
#include <string>
#include <algorithm>
#include <cmath>
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <vector>
#include <bitset>

using namespace std;

#define LL long long
const int INF = 0x3f3f3f3f;
#define MAXN 500
int main()
{
    int n,a,b,c,x;
    scanf("%d%d%d",&n,&a,&b);
    c=0;
    int ans=0;
    int tot=0;
    for(int i=0; i<n; i++)
    {
        scanf("%d",&x);
        tot+=x;
        if(x==1)
        {
            if(a>0)
                a--,ans+=1;
            else if(b>0)
                b--,c++,ans+=1;
            else if( c>0)
                c--,ans++;
        }
        else if(x==2)
        {
            if(b>0)
                b--,ans+=2;
        }
    }
    printf("%d",tot-ans);
        return 0;
}