## https://yukicoder.me/problems/no/2928




def main():
    H, W = map(int, input().split())
    Si, Sj = map(int, input().split())
    Gi, Gj = map(int, input().split())

    Si -= 1
    Sj -= 1
    Gi -= 1
    Gj -= 1

    passed = [[False] * W for _ in range(H)]
    passed[Si][Sj] = True

    def dfs(passed, i0, j0):
        if (i0, j0) == (Gi, Gj):
            return 1

        answer = 0
        for di, dj in ((0, 1), (0, -1), (1, 0), (-1, 0)):
            new_i = di + i0
            new_j = dj + j0
            if 0 <= new_i < H and 0 <= new_j < W:
                if not passed[new_i][new_j]:

                    is_ok = True
                    for di2, dj2 in ((0, 1), (0, -1), (1, 0), (-1, 0)):
                        new_i2 = di2 + new_i
                        new_j2 = dj2 + new_j
                        if 0 <= new_i2 < H and 0 <= new_j2 < W:
                            if (new_i2, new_j2) == (i0, j0):
                                continue

                            if passed[new_i2][new_j2]:
                                is_ok = False
                                break
                    
                    if is_ok:
                        passed[new_i][new_j] = True
                        answer += dfs(passed, new_i, new_j)
                        passed[new_i][new_j] = False
        return answer

    ans = dfs(passed, Si, Sj)
    print(ans)




if __name__ == "__main__":
    main()