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逻辑判断与逻辑语句
判断一个命题的真实性，如果命题为真( True )则执行if的逻辑语句
用法:
if bool_result: # 语法块 do # 业务代码块注意缩进
参数︰
bool_result: 判断结果的真假，布尔类型do: 如果bool_result为True时执行任意python代码返回值: if属于关键字，没有返回值
>>> insane_status = 'hunger >>> if insane_status == 'hunger': print( 'xiaomu invites Insane to dinner' ) xiaomu invites Insane to dinner
实战
# coding:utf-8
info = 'my name is insane'
info_list = info.split()
print(info_list)
if info_list[0] == 'insane':
print(1)
info_list[0] = 'loafer'
if info_list[1] == 'insane':
print(2)
info_list[1] = 'loafer'
if info_list[2] == 'insane':
print(3)
info_list[2] = 'loafer'
if info_list[-1] == 'insane':
print(4)
info_list[-1] = 'loafer'
print(info_list)
info = ' '.join(info_list)
print(info)
info = 'my name is insane, i am a pythoner, i love python'
info_list = info.split()
if info_list[0] in ['python', 'i']:
info_list[0] = '*'
if info_list[1] == 'python' or info_list[1] == 'i':
info_list[1] = '*'
if info_list[2] == 'python' or info_list[2] == 'i':
info_list[2] = '*'
if info_list[3] == 'python' or info_list[3] == 'i':
info_list[3] = '*'
if info_list[4] == 'python' or info_list[4] == 'i':
info_list[4] = '*'
if info_list[5] == 'python' or info_list[5] == 'i':
info_list[5] = '*'
if info_list[6] == 'python' or info_list[6] == 'i':
info_list[6] = '*'
if info_list[7] == 'python' or info_list[7] == 'i':
info_list[7] = '*'
if info_list[8] == 'python' or info_list[8] == 'i':
info_list[8] = '*'
if info_list[9] == 'python' or info_list[9] == 'i':
info_list[9] = '*'
if info_list[-1] in ['python', 'i']:
info_list[-1] = '*'
print(info_list)
info = ' '.join(info_list)
print(info)
info = 'my name is insane'
print(len(info))
if len(info) > 10 and len(info) != 15:
print(info.replace('insane', 'loafer'))
if len(info) > 10 and len(info) != 17:
print(info.replace('name', 'iop'))
print('finish')
['my', 'name', 'is', 'insane'] 4 ['my', 'name', 'is', 'loafer'] my name is loafer ['my', 'name', 'is', 'insane,', '*', 'am', 'a', 'pythoner,', '*', 'love', '*'] my name is insane, * am a pythoner, * love * 17 my name is loafer finish Process finished with exit code 0
