Python Web - L01

from decimal import Decimal

a = Decimal('1.1')

print(type(a),a)

b = Decimal('0.5')

c = Decimal('0.4')

print(b-c)

d = Decimal('0.1')

print(0.1 * 3)

print(d * 3)

_1 = 2 #comment

y = 2

print(id(y))

y = y + 12

print(_1,y)

print(id(_1),id(y))

x = 1

print(type(x), id(x))

x = float(x)

print(type(x), id(x))

x = True

print(type(x), id(x))

print(1 == True)

print(0 != False)

print(1/3 + 1/3 + 1/3)

print(1, 5j)

name = ['John','Amy', 'Peter', [True, 12, 55, ["hello", "world", 3.4, '1'], "Dave"]]

print(name)

print(name[0], id(name[0]), name[1], id(name[1]), name[2], id(name[2]))

age = [30,12,60]

name[1] = age

print(name, name[1], name[1][1])

print(name[3][3][3])

a = 1

print(id(a))

a = 10

print(id(a))

x = ["john", "ann"]

print(id(x),x)

x[0] = ["john", "ann", "peter"]

print(id(x),x)

y = x # x address insert to y. Therefore, y addess equal to x address

print(id(y),y)

x = []

print(id(x))

# The id of x (Line 47) is different with x (Line 49)

x = ["john", "ann", "peter"]

print(id(x))

x = ["john", "ann", "peter"]

print(id(x))

b = "abcdefghijklmnopq"

c = "abcdefghijklmnopq"

print(id(b))

print(id(c))

a = {1,2,3,4,5,6,1,1,2,2,3,4,2,3,1}

print(a)

a = {'apple',1,"dog",2,3,"apple",4,5,6,"dog",1,1,2,2,3,4,2,3,1}

print(a) # The result is random.

# frozenset -> don't let anyone edit the list. if a(frozenset)|b, result is frozenset. if a(normalset)|b(frozenset), result is normalset.

#a = frozenset({'apple',1,"dog",2,3,"apple",4,5,6,"dog",1,1,2,2,3,4,2,3,1})

x = 1

a = {'apple',1,"dog",2,3,"apple",4,5,6,"dog",1,1,2,2,3,4,2,3,1,print(x),} #If python see (), it will handle () firstly. In this case, it will print '1' firstly.

b = frozenset({'cat',7,8,1,2})

union = a | b

print("Union:")

print(union)

intersection = a & b

print("intersection:")

print(intersection)

intersection.remove(1)

print(intersection)

union.remove(1)

print(union)