py笔记

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print(0b100)  # 二进制整数
print(0o100)  # 八进制整数
print(100)    # 十进制整数
print(0x100)  # 十六进制整数

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print(type(100))  # <class 'int'>
print(type(123.45))  # <class 'float'>
print(type('hello, world'))  # <class 'str'>
print(type(True))  # <class 'bool'>

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print(int('100', base=16))  # str->十六进制int
print(bool(1))          # str->bool，True
print(chr(65))           # int->str，输出'd'
print(ord('A'))         # str->int，100

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print(11//3)
print(2 ** 4)

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a = None
print(a := 10)
print(1 <= a <= 2)

b = 11

print('%d 你好 %d' % (a, b))
print(f'{a:d} 你好 {b:.1f}')

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if 1 <= a <= 100:
    print('你好')
elif a and (not b):
    print('你好1')
else:
    if b:
        print('wow')
    else:
        print('now')

match a:
    case 1 | 3: print('1')
    case 2: print('2')

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'''

import time

        # 0 ~ 99

for _ in range (100): # empty, only repeat
    time.sleep(1) # 1s

for i in range (0, 100, 2): # even number
    time.sleep(0.01)

print(sum(range(1, 3, 0.1)))

'''

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while a <= 15:
    a += 1
    if a > 20:
        break
    elif a > 25:
        continue

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import random

a = random.randrange(1, 101)

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items1 = [1, 1.1, '1', True]
items2 = list(range(1, 11))
items3 = list('hello') # h e l l o
print(items1 + items2 + items3 * 2)
print(2 not in items1) # False
print(items1[0], items1[-1]) # forward subscript 0 ~ 4 is equal to reversed subscript -5 ~ -1
print(items1[0:5:2]) # range [0,5), span is 2, namely 0, 2, 4, they can also be negative
print(items1[:], items1[::]) # acquiescently 0, ending, 1
# such options can also be used to modify lists

# lists can be compared, like ==, !=, <= ..., the rule is comparing each elements one by one(parallel[adv])


# type 1 to traverse each one:
for i in range(len(items1)):
    print(items1[i], end = ' ')
# type 2:
for item in items1:
    print(item, end = " ")


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