50分。1，3，4，6，9过了。 调试了1个多小时，实在找不到问题，我个蒟蒻。

#include<iostream>
using namespace std;
int n, m, t, s1x, s1y, f1x, f1y, a1n1s = 0, t1x, t1y, a[10][10], b[10][10];
int d1x[] = {-1, 1, 0, 0};
int d1y[] = {0, 0, -1, 1};
void DFS(int x, int y) {
	if(x == f1x && y == f1y) {
		a1n1s++;
		return;
	}
	for(int i = 0; i < 4; i++) {
		int x1x = x + d1x[i];
		int y1y = y + d1y[i];
		if((x1x >= 1 && x1x <= n && y1y >= 1 && y1y <= m )&& a[x1x][y1y] == 0) {
			a[x1x][y1y] = 1;
			DFS(x1x, y1y);
			a[x1x][y1y] = b[x1x][y1y];
		}
	}
}
int main() {
	cin >> n >> m >> t >> s1x >> s1y >> f1x >> f1y;
	for(int i = 1; i <= t; i++) {
		cin >> t1x >> t1y;
		a[t1x][t1y] = 1;
		b[t1x][t1y] = 1;
	}
	a[s1x][s1y] = 1;
	DFS(s1x, s1y);
	cout << a1n1s;
	return 0;
}