3-课后习题记录-就放这里了

# 1、 使用while循环输入1 2 3 4 5 6   8 9 10
count = 1
while count <= 10:
    if count != 7:
        print(count)
    count += 1

# 2、求1-100的和
count = 1
sum = 0
while count <=100:
    sum += count
    count += 1
print(sum)

# 3、输出1-100的所有奇数
count = 1
while count <= 100:
    if count % 2:
        print(count)
    count += 1

# 4、输出1-100的所有偶数
count = 1
while count <= 100:
    if count % 2 == 0:
        print(count)
    count += 1

# 5、求1-2+3-4+5 ... 99的所有数的和
count = 1
sum = 0
while count < 100:
    if count % 2 ==1:
        sum += count
    else:sum -= count
    count += 1
print(sum)

# 6、用户登录（失败则重试三次）
users = {‘wangjing‘:‘jingjing‘,‘wangxiao‘:‘xiaoxiao‘}

count = 1
while count <=3:
    username = input(‘请输入您的用户名：‘)
    pasword = input(‘请输入您的密码：‘)
    if username in users.keys() and pasword == users[username]:
        print(‘登录成功‘)
    elif count != 3:
        print(‘登录失败，您还可以登录‘ + str(3-count) + ‘次‘)
        count += 1
    else:print(‘登录失败，您不能再登录了‘)