解

#include<bits/stdc++.h>
using namespace std;
int n,m,t;
int arr[0XA][0xA],zhangx,zhangy,sx,sy,ex,ey,ans=0;
bool v[0xA][0xA];
short d[4][2]={{-1,0},{1,0},{0,-1},{0,1}};
void dfs(int x,int y)
{
	v[x][y]=1;
	for(int i=0;i<4;i++)
	{
		int xx=x+d[i][0];
		int yy=y+d[i][1];
		if(xx>=1 &&yy>=1 && yy<=m && xx <=n && arr[xx][yy]!=1 && v[xx][yy]==0)
		{
			if(xx==ex && yy==ey)
			{
				ans++;
			}
			else
			{
				dfs(xx,yy);
			}
		}
	}
	v[x][y]=0;
	return;
}
int main()
{
	cin >> n >> m >> t;
	for(int i=0x1;i<=n;i++)
	{
		for(int j=0x1;j<=m;j++)
		{
			arr[i][j]=0x0;
			v[i][j]=0x0;
		}
	}
	cin >> sx >> sy >> ex >> ey;
	for(int i=0x1;i<=t;i++)
	{
		cin >> zhangx >> zhangy;
		v[zhangx][zhangy]=0x1;
	}
	dfs(sx,sy);
	cout << ans;
}