#include <iostream>
#include <vector>
using Int = long long;
int dx[] = {1, 0, -1, 0};
int dy[] = {0, 1, 0, -1};
int main() {
	int H, W;
	std::cin >> H >> W;
	int Si, Sj;
	std::cin >> Si >> Sj;
	--Si;
	--Sj;
	int Gi, Gj;
	std::cin >> Gi >> Gj;
	--Gi;
	--Gj;
	int ans = 0;
	std::vector vis(H, std::vector(W, false));
	auto dfs = [&](auto dfs, int x, int y) {
		if (x < 0 || y < 0 || x >= H || y >= W ||vis[x][y]) return;
		int cnt = 0;
		for (int i = 0; i < 4; ++i) {
			int xx = x + dx[i];
			int yy = y + dy[i];
			if (xx < 0 || yy < 0 || xx >= H || yy >= W) continue;
			if (vis[xx][yy]) {
				++cnt;
			}
		}
		if (cnt > 1) return;
		if (x == Gi && y == Gj) {
			++ans;
			return;
		}
		vis[x][y] = true;
		for (int i = 0; i < 4; ++i) {
			dfs(dfs, x + dx[i], y + dy[i]);
		}
		vis[x][y] = false;
	};
	dfs(dfs, Si, Sj);
	std::cout << ans << std::endl;
}