print("Hello, World!")
C:\Users\Your Name>python hello.py
Hello, World!
import sys
print(sys.version)
if 5>2:
print ("Five is greater than two!") #if 要縮排, 通常4格
print ("Thank you!") #要相同縮排
"""
THIS
IS
A
MULTI
LINES
COMMENTS
"""
print("Hello World!")
print(1+1) #先運算後出值
x=1
y=1
print(id(x)) # 1放在RAMM, X=1 係話比佢聽1在RAM的地址
print(id(y))
x=x+1 # 加優先過等號
y=1.0
print(x)
print(id(x),id(y))
print(type(x),type(y))
print(x>0)
""
This
is
a test
""
_y=1 #varible only can use_ or letter, double _ build in function
print(0.5-0.4) #0.1 會有誤差
print(0.5-0.2)
print(0.1+0.1+0.1) #0.3 會有誤差
_y=1 #varible only can use_ or letter, double _ build in function
print(0.5-0.4) #0.1 會有誤差
print(0.5-0.2)
print(0.1+0.1+0.1) #0.3 會有誤差
from decimal import Decimal #decimal (Library), Decimal (class)
from math import *
print(globals())
help(sin)
x=Decimal("0.1")
y=Decimal(0.1)
print(x,type(x))
print(y,type(y))
print(sqrt(1+1))
x="Hello"
print(type(x),id(x))
print(x[0])
#x[0]=S 因為佢成舊放响RAM, 所以冇得只改一個字母
x="Sello"
print(x,id(x))
--------------------
def a():
'''
+++ HELP +++
+++ HELP +++
+++ HELP +++
'''
x=1
help(a)
-----------------------------
def a():
x='''
+++ HELP +++
+++ HELP +++
+++ HELP +++
'''
print(x)
a()
----------------------------
# \ 係continue line, \後面不能有space
x=1+1+1+1+1+1+1+1+ \
+1+1+1
print(x)
------------------------------
x=True #internal 係1
y=False #internal 係0
print(1==True)
print(0==False)
print(1!=False)
print(0!=True)
print(True+False)
print(x+y)
print(x+x)
#一個等如用黎做assignment, 兩個等如用黎做比較
x=[1,2,3]
y=[4,5,6]
---------------------------------------------
#expression_result=7-4+3*6/2**2%5
expression_result=(7-4)+(((3*6)/(2**2))%5)
expression_result=((10+(3*2))<20) and ((15%4)==3)) or (not ((5-(3*2))>0))
result = not (10 // 3) == 3 or ((8 %3) +1) == 3 and 7 | 2 > 5
result4 = (5 + 3) (if ((2 ** 3) > 7) else ((4 * 6) (if (7 < 8) else (5 - (10 /2))))
result2 = 10 > 5 and 3 * 3 + 1 <= 10 or not 5 != 5 and 4 * 2
result1 = 3+5**2&15|2**3 if 8%3 >1 else 1^7&4
#PEP8 (optional)
# "None" is a special data type
#3,8-11 少用
name='PERCY'
age=6
print('Hi! '+ name + str(age))
print(f'Hi! ', {name} , {age})
print(type(str(1.0)))
print(int(float('1.1')))
print(float(1),float(1.1),float(True))
print(float(1),float(1.1),float(False))
print(bool(1),bool(2.1),bool('a'),bool('')) #不是0就是 True, 空格,None False
name=["john","peter","ann","dave"] #list 所有都是地址
print(id(name),type(name))
print(name[0],name[1],name[2],name[3])
name=["john",10,10,None]
print(name[0],id(name[1]),id(name[2]),name[3])
name=["john",["john",10,10,None],[1,2,3,4], None]
name[2][0]=20
print(name)
print (name[2])
print (name[0])
name=["john",["john",['a','b','c'],[[1,2,3]],None]]
print(name[1][0][2])
name=["john",["john",['a','b','c'],[[1,2,3]],None]]
print(name[1][0][2])
t=1,2,3
print(type(t),t)
t=1,
print(type(t),t[0])
print(type(t),t[0],t)
a,b=1,2 #turple
print(a,b)
a,b=[1,2],[2,3] #list is address
print(a,b)
a=[1,2],[2,3]
print(a,b)
#Tuple
a,b=1,2 #tuple
a,b = a+b , a*b #a,b = 1+2,1*2 = 3,2
a,b = [a,b],[b,a] #a,b = [3,2] [2,3]
#a,b = a #a,b=[3,2]
#a,a = a
print(a,b)
#Tuple
#SET 大{} filter 走相同value
s = {1,2,3,4,5,6,7,1,2,1,2,1,2,3,3,4,4,4,5,6,6,7,7}
print(s)
s = {1,2,3,'a',5,6,7,1,2,1,'b',1,2,3,3,4,4,4,5,6,6,7,7}
print(s)
s = [1,2,3,'a',5,6,7,1,2,1,'b',1,2,3,3,4,4,4,5,6,6,7,7] #把list相同值filter走
print(list(set(s)))
