python基础笔记

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==和is

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# == 和 !=比较的是赋值是否相等
# is 和 not比较的是id是否相等，是否是同一个对象
a = [1, 2, 3]
b = [1, 2, 3]
print(a == b)
print(a is b)
print(id(a), id(b))

range 序列

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# range： 起始位置、结束位置、步长
print(range(3, 10))
print(list(range(3, 10, 2)))
r = range(10)
print(r)
print(list(r))

# 通过range进行for 循环
for i in range(100):
    print(i)

while 语句

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# while语句
i = 0
total = 0
while i < 100:
    i += 1
    total += i

print(total)

# break
i = 0
while i < 100:
    i += 1
    if i > 50:
        break
print(i)

# continue
i = 0
while i < 100:
    i += 1
    if i % 10:
        continue
    print(i)

三元运算

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a = 1
b = 2
max = a if (a > b) else b
print(m)