Python中字符串和列表去重方法总结

# *_* coding : UTF-8 *_*

​​​​​​​name='王李张李陈王杨张吴周王刘赵黄吴杨'
newname=''
for char in name:
    if char not in newname:
        newname+=char
print (newname)

# *_* coding : UTF-8 *_*

​​​​​​​name='王李张李陈王杨张吴周王刘赵黄吴杨'
newname=''
i = len(name)-1
while True:
    if i >=0:
        if name[i] not in newname:
            newname+=(name[i])
        i-=1
    else:
        break
print (newname)

# *_* coding : UTF-8 *_*

​​​​​​​name = '王李张李陈王杨张吴周王刘赵黄吴杨'
myname = set(name)
print(myname)
newname = list(set(name))
print(''.join(newname))
newname.sort(key=name.index)
print(newname)
print(''.join(newname))

# *_* coding : UTF-8 *_*

​​​​​​​name='王李张李陈王杨张吴周王刘赵黄吴杨'
l = len(name)        # 字符串下标总长度
for s in name:
    if name[0] in name[1:l]:
        name = name[1:l]
    else:
        name= name[1:l]+name[0]
print(name)

# *_* coding : UTF-8 *_*

name='王李张李陈王杨张吴周王刘赵黄吴杨'
zd={}.fromkeys(name)
mylist=list(zd.keys())
# mylist = list({}.fromkeys(name).keys())
print (''.join(mylist))

# *_* coding : UTF-8 *_*

city=['上海', '广州', '上海', '成都', '上海', '上海', '北京', '上海', '广州', '北京', '上海']
ncity = [] # 定义一个空列表
for item in city: # 遍历列表city
    if item not in ncity: # 如果item不在ncity，则添加到ncity
        ncity.append(item)
print (ncity)

# *_* coding : UTF-8 *_*

city=['上海', '广州', '上海', '成都', '上海', '上海', '北京', '上海', '广州', '北京', '上海']
ncitx=list(set(city))
print(ncitx)

# *_* coding : UTF-8 *_*

city=['上海', '广州', '上海', '成都', '上海', '上海', '北京', '上海', '广州', '北京', '上海']

ncitx=list(set(city))
ncitx.sort( key=city.index)
print(ncitx)

# *_* coding : UTF-8 *_*

city=['上海', '广州', '上海', '成都', '上海', '上海', '北京', '上海', '广州', '北京', '上海']
city.sort()
for x in city:
     while city.count(x)>1:
         del city[city.index(x)]

print(city)

# *_* coding : UTF-8 *_*

city=['上海', '广州', '上海', '成都', '上海', '上海', '北京', '上海', '广州', '北京', '上海']
mylist = list({}.fromkeys(city).keys())  # fromkeys() 函数创建一个新字典，获取新字典的键（唯一值）
print (mylist)