Flip Flow

答案如下：

#include
using namespace std;
int main()
{
	int now,twice,up=0,down=0;
	int change[1005]={0};
	scanf("%d%d%d",&now,&down,&twice);
	for(int i=0;i<twice;i++)
	  scanf("%d",&change[i]);
	int next=0;  
	for(int t=0;t<now;t++)
	{
		if(t==change[next])
		{
			int temp=up;
			up=down;
			down=temp;
			next++;
		}
		if(up!=0)
		{
			up--;
			down++;
		}
	}
	printf("%d",up);
	return 0;
}