#include <stdio.h>
int main()
{
	freopen("RT.in","r",stdin);
	freopen("RT.out","w",stdout);
	int _a,_b,a[20000]={0},b[20000]={0},n[20000]={0},_n,un=0,_un=1;
	scanf("%d%d%d",&_n,&_a,&_b);
	for (int i = 0; i < _n; ++i)
		scanf("%d",&n[i]);

	for (int i = 0; i < _n; ++i)
	{
		_un=1;
		if (n[i]==1)
		{
			for (int j = 0; j < _a; ++j)
			{
				if (a[j]==0)
				{
					a[j]=1;
					_un=0;
					break;
				}
			}
			if (_un!=0)
			{
				for (int j = 0; j < _b; ++j)
				{
					if (b[j]==0)
					{
						b[j]=1;
						_un=0;
						break;
					}
				}
			}
			if (_un!=0)
			{
				for (int j = 0; j < _b; ++j)
				{
					if (b[j]==1)
					{
						b[j]=2;
						_un=0;
						break;
					}
				}
			}
		}
		if (n[i]==2)
		{
			_un=2;
			for (int j = 0; j < _b; ++j)
			{
				if (b[j]==0)
				{
					b[j]=2;
					_un=0;
					break;
				}
			}
		}
		if (_un==1)
			un++;
		if (_un==2)
			un+=2;
	}
	printf("%d\n",un );
	return 0;
}