python_集合

>>> import random
>>> import time
>>> x=list(range(10000))
>>> y=set(range(10000))
>>> z=dict(zip(range(1000),range(10000)))
>>> r=random.randint(0,9999)
>>>
>>> start = time.time()
>>> for i in range(9999999):
r in y

>>> print('list,time used:',time.time()-start)
list,time used: 89.40382695198059
>>>
>>> start = time.time()
>>> for i in range(9999999):
r in z

>>> s={1,2,3}
>>> s.add(3)
>>> s.add(4)
>>> s
{1, 2, 3, 4}
>>> s.update({3,4})
>>> s
{1, 2, 3, 4}
>>> s.discard(5)
>>> s
{1, 2, 3, 4}

>>>

>>>

>>> a_set=set([8,9,10,11,12,13])
>>> b_set={0,1,2,3,7,8}
>>> a_set | b_set
{0, 1, 2, 3, 7, 8, 9, 10, 11, 12, 13}
>>> a_set.union(b_set)
{0, 1, 2, 3, 7, 8, 9, 10, 11, 12, 13}
>>> a_set & b_set
{8}

>>> a_set.intersection(b_set)
{8}
>>> a_set.difference(b_set)
{9, 10, 11, 12, 13}
>>> b_set.difference(a_set)
{0, 1, 2, 3, 7}
>>> a_set-b_set
{9, 10, 11, 12, 13}
>>> a_set+b_set

{0, 1, 2, 3, 7, 8, 9, 10, 11, 12, 13}
>>> a_set ^ b_set
{0, 1, 2, 3, 7, 9, 10, 11, 12, 13}
>>> x={1,2,3}
>>> y={1,2,5}
>>> z={1,2,3,4}
>>> x<y
False
>>> x<z
True
>>> x.issubset(y)
False
>>> x.issubset(z)
True
>>> from enum import Enum
>>> class Color(Enum):
red=1
blue=2
green=3

>>> Color.red
<Color.red: 1>
>>> type(Color.red)
<enum 'Color'>
>>> isinstance(Color.red,Color)
True

>>> x=dict()
>>> x[Color.red]='red;'
>>> x
{<Color.red: 1>: 'red;'}
>>> Color(2)
<Color.blue: 2>
>>> Color['red']
<Color.red: 1>
>>> r=Color.red
>>> r.name
'red'
>>> r.value
1
>>> list(Color)
[<Color.red: 1>, <Color.blue: 2>, <Color.green: 3>]
>>>
>>>
>>> import random
>>> listRandom=[random.choice(range(10000)) for i in range(100)]
>>> noRepeat=[]
>>> for i in listRandom:
if i not in noRepeat:
noRepeat.append(i)

>>>
>>>
>>> newSet=set(listRandom)
>>> newSet
{1024, 3592, 8212, 1051, 3612, 5679, 2608, 8241, 1590, 6199, 4158, 4679, 3658, 596, 1628, 95, 3168, 5733, 3176, 1646, 2163, 5750, 4222, 5768, 7309, 6804, 8341, 8348, 3741, 1189, 1704, 1705, 2732, 7342, 693, 7351, 1208, 5831, 2249, 1229, 6863, 8912, 2776, 729, 5340, 736, 8937, 8427, 4851, 2294, 3830, 3852, 5904, 278, 7458, 2345, 2859, 2867, 307, 3381, 318, 5443, 3396, 1864, 859, 5472, 8032, 867, 4453, 1381, 8559, 5487, 6002, 6003, 4981, 6007, 6008, 3455, 2953, 1929, 9107, 7582, 9630, 4007, 432, 948, 1981, 5064, 9674, 4047, 464, 5074, 3029, 3031, 8664, 473, 2546, 5619, 9203}

>>> def RandomNumbers1(number,start,end):
data=[]
while True:
element=random.randint(start,end)
if element not in data:
data.append(element)
if len(data)==number:
break
return data

>>> def RandomNumbers2(number,start,end):
data=set()
while True:
element=random.randint(start,end)
data.add(element)
if len(data)==number:
return data

>>> start=time.time()
>>> for i in range(1000):
d1=RandomNumbers1(500,1,10000)

>>> print('Time used:',time.time()-start)
Time used: 105.95552897453308
>>> start=time.time()
>>> for i in range(1000):
d2=RandomNumbers2(500,1,10000)
print('Time used:',time.time()-start)

>>> {str(x) for x in range(10)}
{'8', '9', '2', '4', '7', '0', '1', '5', '6', '3'}