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"""
#any while do loop in python?
# can we modify the code?
min_length =2
name = input('Please enter your name:')
while not(len(name) >= min_length \
and name.isprintable() and name.isalpha()):
name = input('Please enter your name:')
print('Hello,{0}'.format(name))
"""
"""
#example 2
a = 0
while a < 10:
a += 1
if a % 2:
continue # 直接run while 语句
print(a)
"""
"""
l=[1,2,3]
val=1
found = False
idx=0
while idx < len(l):
if l[idx] == val:
found = True
break #break will exit the whole while block
idx += 1
if found:
l.append(val)
print(l)
"""
"""
#while-else block
l= [1,2,3]
val=1
idx=0
while idx < len(l):
if l[idx] == val:
break #break,EXIT退出最近这一层的loop循环. will exit the whole while-else block
idx += 1
else: #idx >= len(1)时会执行这个 else block,执行完会exit the whole while-eles block
l.append(val)
print(l)
#The else blcok will not be executed if the loop is stopped by a break statement
"""
"""
#tenary opreator : if
a = 1
b=10 if a==1 else 0
print(b)
"""
"""
a = 1
b= a+1 if a==1 else a-1
print(b)
# the above blcok is same to below.
a=1
if a==1:
b= a+1
else:
b= a-1
print(b)
"""
"""
a=330
b=330
#print("A") if a > b else print("=") if a == b else print("B") #will excute (if a == b else print("B")) first.从右到左excute
(print("A") if a > b else print("=")) if a == b else print("B")
"""
"""
for x in range(6):
print(x)
else:
print("Finally finished")
"""
"""
a=[1,2,3]
c=[1,2,3]
b=a
print(a is b) #is check the address is same or not.
print(a is c) #is check the address is same or not.
print(a == c) # == check the value is same or not.
d=10
print(d == 10)
print (d is 10) #check address
"""
#integer base
"""
print(int("101",2))
print(int("101",8))
print(type(3+2)) #integer
print(type(3**2)) #integer
print(type(6/3)) # always float
import math
x=math.floor(3.999)
y=math.floor(-3.15)
print(x)
print(y) #-4
"""
"""
import math
a=33
b=16
print(a/b) #2.0625
print(a//b) #2
print(math.floor(a/b)) #2
#division operator a//b = math.floor(a/b) only for positive division.
a=-33
b=16
print('{0}/{1}={2}'.format(a,b,a/b)) #-2.0625
print('trunc({0}/{1})={2}'.format(a,b,math.trunc(a/b))) #-2
print('{0}//{1} = {2}'.format(a,b,a//b)) #-3
print('floor({0}//{1})={2}'.format(a,b,math.floor(a/b))) #-3
print(a%b) #15
#modulo opeartor : a =b*(a//b)+a%b --> -33 = 16*(-3)+ a%b --> a%b=15
#a%b：a/b的余数
# a//b: a/b的商数
print(a==b*(a//b)+a%b)
"""
"""
x=0.1+0.1+0.1 #0.30000000000000004
y=0.3
print(format(x,'.20f'))
print(format(y,'.20f'))
print(0.1+0.1+0.1==0.3) #电脑用分数来近似小数，所以存在误差，比如0.125=1/8，0.0625=1/16，所以0.1= 1/16+另一个更小的分数比如1/32
print(0.25+0.25+0.25+0.25)
a=10000.1+10000.1+10000.1
b=30000.3
print(format(a,'.20f'))
print(format(b,'.20f'))
print(10000.1+10000.1+10000.1-30000.3) #3.637978807091713e-12
print(7.1+7.1+7.1==21.3) #False
import math
print(math.pi)
"""
Python
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