h,w = map(int,input().split())
sx,sy =  map(int,input().split())
gx,gy =  map(int,input().split())
sx -= 1
sy -= 1
gx -= 1
gy -= 1

# ↑→↓←
dx = [-1,0,1,0]
dy = [0,1,0,-1]
used = [[0 for j in range(w)]for i in range(h)]
used[sx][sy] = 1
ans = 0
def isvalid(x,y):
    return 0<=x<h and 0<=y<w

def canmove(x,y):
    if(used[x][y]):
        return
    
    cnt = 0
    for k in range(4):
        nx = x + dx[k]
        ny = y + dy[k]
        if(isvalid(nx, ny)):
            cnt += used[nx][ny]
    
    return cnt <= 1
    
def dfs(x,y, used):
    global ans
    if(x == gx and y == gy):
        ans += 1
        return
    
    for k in range(4):
        nx = x + dx[k]
        ny = y + dy[k]
        if(isvalid(nx, ny)):
            if(canmove(nx, ny)):
                used[nx][ny] = 1
                # for i in range(h):
                #     for j in range(w):
                #         print(used[i][j], end=" ")
                #     print()
                # print("---")
                dfs(nx, ny, used)
                used[nx][ny] = 0
                

dfs(sx, sy, used)
print(ans)