python-逻辑结构操作

0x01 大纲

逻辑结构

list

dict

判断if else elif

break

continue

while

0x02 添加

list = [i for i in range(0,10)]
print(list)

empty_list=[]
for i in range(0,10):
    empty_list.append(i)

print(empty_list)

输出

[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

在python中布尔值为大写True和False

num = 0
while True:
    print('真')
    num+=1
    if num > 10:
        break

0x03 continue

for i in range(0,5):
    if i==3:
        continue
    print(i)

输出

0

1

2

4

0x04 if判断规则

inputTest = input('please input >>>')
if inputTest == '1':
    print('u input is 1')
elif inputTest == '2':
    print('u input is 2')
else:
    print('no input')

输出

please input >>>1

u input is 1

但是如果把elif改为if的话 那么else就是匹配最近的if 和上面的if为两个不同的逻辑结构了

inputTest = input('please input >>>')
if inputTest == '1':
    print('u input is 1')
if inputTest == '2':
    print('u input is 2')
else:
    print('no input')

输出

please input >>>1

u input is 1

no input

0x05 if elif

if elif 满足第一个就不执行后面了

inputTest = input('please input >>>')
if inputTest == '1':
    print('u input is 1')
elif inputTest == '1':
    print('u input is one')
else:
    print('no input')

输出

please input >>>1

u input is 1

0x06 操作字典

dictTest = {'1':1,'2':2,'3':3}
for k,v in dictTest.items():
    print(k,v)

输出

1 1

2 2

3 3

只输出键

dictTest = {'1':1,'2':2,'3':3}
for k in dictTest.keys():
    print(k)

只输出值

dictTest = {'1':1,'2':2,'3':3}
for v in dictTest.values():
    print(v)