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names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"] #列表存储,类似数组
names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"] #列表存储,类似数组print(names[1],names[3]) #取值,1、3代表下标,从左到右的位置执行结果:Guyun Xuliangchenprint(names[1:3]) #切片,顾头不顾尾取[1]、[2]的值print(names[0:3]) #切片print(names[:3]) #等同于0:3,从下标0到3print(names[-1]) #切片,取倒数第一个值print(names[-2]) #取倒数第二个值print(names[-2:]) #取最后两个值
names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]names.append("LeiHaidong") #追加到最后print(names)执行结果:['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen', 'LeiHaidong']
names.insert(1,"Chenronghua") #数据插入,插在哪个位置前面就写这个元素的下标,如插在Guyun前面names.insert(3,"Xinzhiyu") #插在Guyun后面print(names)执行结果:['ZhangYang', 'Chenronghua', 'Guyun', 'Xinzhiyu', 'Xiangpeng', 'Xuliangchen', 'LeiHaidong']
names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]print(names)print(names.index("Xiangpeng")) #查出Xiangpeng的位置print(names[names.index("Xiangpeng")]) #获取下标内容执行结果:['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen']2Xiangpeng
names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]print("count-->",names.count("ZhangYang"))执行结果:count--> 1
names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]names.reverse()print(names)执行结果:['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen']reverse--> ['Xuliangchen', 'Xiangpeng', 'Guyun', 'ZhangYang']
names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]names2 = [1,2,3,4]print(names)names.extend(names2)print("extend-->",names)执行结果:['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen']extend--> ['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen', 1, 2, 3, 4]
names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]names.sort()print(names)执行结果:['Guyun', 'Xiangpeng', 'Xuliangchen', 'ZhangYang']
names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]names.clear()print(names)执行结果:[]
names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]names2 = names.copy()print(names)print(names2)names[1] = "古云" #更改Guyun,可以看到names2中并没有修改print("names-->",names)print("names2-->",names2)执行结果:['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen']['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen']names--> ['ZhangYang', '古云', 'Xiangpeng', 'Xuliangchen']names2--> ['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen']
names = ["ZhangYang","Guyun",["alex","jack"],"Xiangpeng","Xuliangchen"] names2 = names.copy()print(names)print(names2)names[1] = "古云"names[2][0] = "ALEX" #更改列表中的alex为ALEX,可以看到names2中也相应更改print("names-->",names)print("names2-->",names2)执行结果:['ZhangYang', 'Guyun', ['alex', 'jack'], 'Xiangpeng', 'Xuliangchen']['ZhangYang', 'Guyun', ['alex', 'jack'], 'Xiangpeng', 'Xuliangchen']names--> ['ZhangYang', '古云', ['ALEX', 'jack'], 'Xiangpeng', 'Xuliangchen']names2--> ['ZhangYang', 'Guyun', ['ALEX', 'jack'], 'Xiangpeng', 'Xuliangchen']★★★★注意:这里的的copy只会拷贝第一层,列表中包含列表,其中列表是指向存放列表的内存地址,所以在更改列表中的元素时,拷贝的部分也会相应地更改。为了实现深入拷贝,可以导入copy模块:import copynames2 = copy.deepcopy(names)print(names)print(names2)names[1] = "古云"names[2][0] = "ALEX"print("names-->",names)print("names2-->",names2)执行结果:['ZhangYang', 'Guyun', ['alex', 'jack'], 'Xiangpeng', 'Xuliangchen']['ZhangYang', 'Guyun', ['alex', 'jack'], 'Xiangpeng', 'Xuliangchen']names--> ['ZhangYang', '古云', ['ALEX', 'jack'], 'Xiangpeng', 'Xuliangchen']names2--> ['ZhangYang', 'Guyun', ['alex', 'jack'], 'Xiangpeng', 'Xuliangchen']可以看到拷贝是完全克隆过来的,但是生产过程中一般不会使用,拷贝多一份数据,等于多占据了一份内存空间。
names = ["ZhangYang","Guyun",["alex","jack"],"Xiangpeng","Xuliangchen"] for i in names: print(i)执行结果:ZhangYangGuyun['alex', 'jack']XiangpengXuliangchen
names = ["ZhangYang","Guyun",["alex","jack"],"Xiangpeng","Xuliangchen"] print(names[0:-1:2]) #打印第一个到最后一个,步长为2执行结果:['ZhangYang', ['alex', 'jack']]
程序:购物车程序
需求:
启动程序后,让用户输入工资,然后打印商品列表
允许用户根据商品编号购买商品
用户选择商品后,检测余额是否够,够就直接扣款,不够就提醒
可随时退出,退出时,打印已购买商品和余额
#!/usr/bin/python# _*_ coding:utf-8 _*_# Aothr: Kimgoods_list = [ ['Iphone',5800], ['Mac pro',9800], ['Bike',800], ['Watch',10600], ['Coffee',31], ['Alex Python',120]]shopping_list = [] #此列表为空当做购物车使用salary = input("Please input your salary:")if salary.isdigit(): salary = int(salary) while True: for index,item in enumerate(goods_list): #enumerate可以取出列表的下标和内容 print(index,item) user_choice = input("请选择你需要的商品编号:") if user_choice.isdigit(): user_choice = int(user_choice) if user_choice = 0: #len可以取出列表的长度 g_item = goods_list[user_choice] if g_item[1]
来自 “ ITPUB博客 ” ,链接:https://blog.itpub.net/625/viewspace-2802745/ ,如需转载,请注明出处,否则将追究法律责任。