x, y = map(int, input().split()) a, b = map(int, input().split()) c, d = map(int, input().split()) e, f = map(int, input().split()) n = [] z = 0 for i in range(x): n.append(0) for i in range(x): if i in range(a, b+1): n[i] = 1 if i in range(c, d+1): n[i] = 1 if i in range(e, f+1): n[i] = 1 for i in range(x): if n[i] == 0: z += 1 print(z+1)

求问错误在哪