#coding=utf-8#sequence(列表和元祖),操作(indexing,slicing,adding,multiplying)#indexinggreeting="Hello"PRint greeting[0] #索引從左至右,是0開始,0,1,...print greeting[-1] #為了區(qū)分0,字符串從右邊計(jì)數(shù)為-1,-2,...'''C:/Python27/python.exe C:/Users/lenovo/PycharmProjects/myprojects/testHo'''#slicingnumbers=[1,2,3,4,5,6,7,8,9,10] #元祖print numbers[3:6] #左閉右開,從左至右數(shù)值變大print numbers[-3:-1] #[x:y] y永遠(yuǎn)比x大print numbers[-3:0] #0對應(yīng)[1],-3對應(yīng)[8],順序一直都是從左至右,因此找不到0下標(biāo)對應(yīng)值為空print numbers[-3:] #[x:y]可以想象y為無窮大,一直索引到最后'''[4, 5, 6][8, 9][][8, 9, 10]''''''numberes[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]下標(biāo)1: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9下標(biāo)2:-10,-9,-8,-7,-6,-5,-4,-3,-2,-1'''print numbers[0:8:2] #[x:y:z],左閉右開,x左邊界,y右邊界,z為步長print numbers[8:3:-2] #從右至左,三坐標(biāo)索引,左邊界值大于右邊界print numbers[:: 4] #步長大于0,從左至右print numbers[::-2] #步長小于0,從右至左'''[1, 3, 5, 7][9, 7, 5][1, 5, 9][10, 8, 6, 4, 2]'''#addinga=[1,2,3]b=[4,5,6]c="Hello"d=a+bprint a+b #相同類型相加# print a+c #不相同類型不可相加'''print a+c[4, 5, 6]TypeError: can only concatenate list (not "str") to list[1, 2, 3, 4, 5, 6]'''#multiplyingstring ='python'num=[42]print string*5print num*10'''pythonpythonpythonpythonpython[42, 42, 42, 42, 42, 42, 42, 42, 42, 42]'''
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