3.3 选择(分支)结构¶

# 仅用于语法展示，请示要运行

if 条件测试表达式1:
    语句块1
elif 条件测试表达式2:
    语句块2
elif 条件测试表达式3:
    语句块3
    ……
else:
    语句块n

score = int(input())  # 输入一个整数表示成绩
if score > 100 or score < 0:  # 区间为score < 0 或score > 100
    result = 'Data error!'
elif score >= 90:  # 区间为90 =< score <= 100
    result = 'A'
elif score >= 80:  # 区间为80 =< score < 90
    result = 'B'
elif score >= 70:  # 区间为70 =< score < 80
    result = 'C'
elif score >= 60:  # 区间为60 =< score < 70
    result = 'D'
else:              # 区间为0 =< score < 60
    result = 'E'
print(result)

# if condition1:
#     # 当 condition1 为 True 时执行的代码
#     pass
# elif condition2:
#     # 当 condition1 为 False 且 condition2 为 True 时执行的代码
#     pass
# elif condition3:
#     # 当前面的条件都为 False，且 condition3 为 True 时执行的代码
#     pass
# else:
#     # 当所有的条件都为 False 时执行的代码
#     pass

# 不推荐使用以下方法：
score = int(input())  # 输入一个整数表示成绩
if score > 100 or score < 0:  # 区间为score < 0 或score > 100
    print('Data error!')
elif score >= 90:  # 区间为90 =< score <= 100
    print('A')
elif score >= 80:  # 区间为80 =< score < 90
    print('B')
elif score >= 70:  # 区间为70 =< score < 80
    print('C')
elif score >= 60:  # 区间为60 =< score < 70
    print('D')
else:              # 区间为0 =< score < 60
    print('E')

# 补充你的代码，使用变量名 price 表示票价，height 表示身高

price = 
height = 

score = int(input())
if score > 100:    # 区间score > 100
    result = '最高分不能超过100'
elif score >= 90:  # 区间为90 =< score <= 100
    result = 'A'
elif score >= 80:  # 区间为80 =< score < 90
    result = 'B'
elif score >= 70:  # 区间为70 =< score < 80
    result = 'C'
elif score >= 60:  # 区间为60 =< score < 70
    result = 'D'
elif score >= 0:   # 区间为0 =< score < 60
    result = 'E'
else:              # 区间为score < 0
    result = '分数不能为负数'
print(result)

score = int(input())
if score >= 60:
    print('成绩合格')
else:
    print('不合格')

score = int(input())

if score > 100 or score < 0:   # score < 0 或score > 100
    print('异常成绩')
else:
    print('正常成绩')

score = int(input())
if 0 <= score <= 100:   # score >= 0 and score <= 100
    print('正常成绩')
else:
    print('异常成绩')

score = int(input())
if score >= 0 and score <= 100:  # pycharm中可同时按alt+shift+enter自动转为链式操作 if 0 <= score <= 100:
    print('正常成绩')
else:
    print('异常成绩')

# 补充你的代码

# 补充你的代码

score = int(input())
if score > 100 or score < 0:
    result = 'Data error!'
else:                            # 此分支下0 =< score <= 100
    if score >= 90:              # 此分支下90 =< score <= 100
        result = 'A'
    else:                        # 此分支 0 =< score < 90
        if score >= 80:          # 此分支下80 =< score < 90
            result = 'B'
        else:                    # 此分支 0 =< score < 80
            if score >= 70:      # 此分支下70 =< score < 80
                result = 'C'
            else:                # 此分支 0 =< score < 70
                if score >= 60:  # 此分支下60 =< score < 70
                    result = 'D'
                else:            # 此分支 0 =< score < 60
                    result = 'E'
print(result)

score = int(input())
if score >= 60:
    print('成绩合格')

# 补充你的代码

score = int(input())
if 0<=score <= 100:
    print('成绩合法')

score = int(input())     # int()函数将输入的整数字符串转换成整数
if 90 <= score <=100:    # 等价于score >= 90 and score <= 100
    result = 'A'
if 80 <= score < 90:
    result = 'B'
if 70 <= score < 80:
    result = 'C'
if 60 <= score < 70:
    result = 'D'
if 0 <= score < 60:
    result = 'E'
if score < 0 or score > 100:
    result = 'Data error!'
print(result)

score = int(input())     # int()函数将输入的整数字符串转换成整数
if 90 <= score <= 100:    # 等价于score >= 90 and score <= 100
    print('A')
if 80 <= score <= 90:
    print('B')
if 70 <= score <= 80:
    print('C')
if 60 <= score <= 70:
    print('D')
if 0 <= score <= 60:
    print('E')
if score < 0 or score > 100:
    print('Data error!')

# 语法格式，不要运行此单元

x if 条件 else y

m, n = eval(input())  # 输入用逗号分隔的两个整数，输出其中较大的值
if m > n:
    max_number = m
else:
    max_number = n
print(max_number)

m, n = eval(input())  # 输入用逗号分隔的两个整数，输出其中较大的值
max_number = m if m > n else n
print(max_number)

username = input()  # 输入表示用户名的字符串
print("用户名正确") if username == 'admin' else print("用户名错误")