four=[1,0,-1,0,1]
def dfs(grid,x,y):
	if grid[x][y]==1:
		return 0
	if not (1<=x<=H-2 and 1<=y<=W-2):
		return 0
	cnt=0
	for i in range(4):
		cnt+=grid[x+four[i]][y+four[i+1]]
	if cnt>=2:
		return 0
	if x==Gi and y==Gj:
		return 1
	grid[x][y]=1
	ret=0
	for i in range(4):
		ret+=dfs(grid,x+four[i],y+four[i+1])
	grid[x][y]=0
	return ret
H,W=map(int,input().split())
H+=2
W+=2
Si,Sj=map(int,input().split())
Gi,Gj=map(int,input().split())
print(dfs([[0]*W for i in range(H)],Si,Sj))