Python02input Function's use operator arithmetic operator assignment operator comparison operator Boolean operator bit operator priority
effect ： Used to accept user input
The return value is str
Use = Assignment variable storage
# Input function input
present = input(' What gift do girls want ？')
print(present, type(present))# It is required to enter two integers from the keyboard , To calculate the sum of two integers
a = input(' Please enter an addend :')
a = int(a) # Store the converted results in a
b = int(input(' Please enter another addend :'))
print(type(a), type(b))
print(a+b)# Add, subtract, multiply and divide print(1+1) # Perform addition operations print(1-1) # Perform subtraction print(2*4) # Perform multiplication print(1/2) # Perform Division print(11//2) # Division operation # Take over operations print(11%2) # Take over operations # Power operation print(2**2) # It means 2 Of 2 Power print(2**3) # It means 2 Of 3 Power
print(9//4) # 2 print(-9//-4) # 2 print(9//-4) # -3 print(-9//4) # -3 # Integers ： One positive and one negative rounded down print(9 % -4) # -3 # The formula ： remainder = Divisor - Divisor * merchant 9-（-4）*（-3）== -3 print(-9 % 4) # 3 # -9-4*（-3）== 3
# Assignment operator , The operation order is from right to left
i = 3+4
print(i)
# Support chain assignment
a = b = c = 20
print(a, id(a))
print(b, id(b))
print(c, id(c))
# Support parameter assignment
a = 20
a += 30 # amount to a = a+30=50
print(a)
a -= 10
print(a)
a *= 2
print(a) # int
print(type(a))
a /= 3
print(a)
print(type(a))
a //= 2
print(a)
a %= 3
print(a)
# Support series unpacking assignment
a, b, c = 20, 30, 40
print(a, b, c)
# Exchange the values of two variables
a, b = 10, 20
print(" Before the exchange ：", a, b)
# In exchange for
a, b = b, a
print(" After the exchange ：", a, b)# Comparison operator , The result of the comparison operator is bool type
a, b = 10, 20
print("a>b Do you ", a > b) # False
print("a<b Do you ", a < b) # True
print("a<=b Do you ", a <= b) # True
print("a>=b Do you ", a >= b) # False
print("a==b Do you ", a == b) # False
print("a!=b Do you ", a != b) # True
''' One = Is assignment operator , Two == Is a comparison operator
A variable has three parts ： identification , type , value
== Is it a value or an identifier that is compared ？ Compare values
The identity of the comparison object uses is
'''
a = 10
b = 10
print(a == b) # True explain ：a And b Of value equal
print(a is b) # True explain ：a And b Of id Identity equality
lst1 = [11, 22, 33, 44]
lst2 = [11, 22, 33, 44]
print(lst1 == lst2) # value
print(lst1 is lst2) # id
print(id(lst1))
print(id(lst2))
print(a is not b) # False a Of id And b Of id It's not equal
print(lst1 is not lst2) #True# Boolean operator
a, b = 1, 2
print('-------------and also ----------------------------')
print(a == 1 and b == 2) # True True and True -->True
print(a == 1 and b < 2) # False True and False -->False
print(a != 1 and b == 2) # False False and True -->False
print(a != 1 and b != 2) # False False and False -->False
print('-------------or perhaps ------------------------------')
print(a == 1 or b == 2) # True True or True -->True
print(a == 1 or b < 2) # True True or False -->True
print(a != 1 or b == 2) # True False or True -->True
print(a != 1 or b != 2) # False False or False -->False
print('-------------not Not Yes bool Negate type operands ----------------------')
f = True
f2 = False
print(not f)
print(not f2)
print('-----------------in And not in------------------------------------')
s = 'helloworld'
print('w' in s)
print('k' in s)
print('w' not in s)
print('k' not in s)Convert data into binary for calculation
# An operator print(4 & 8) # And &, The corresponding digits are 1, As a result, the number is 1, Otherwise 0 print(4 | 8) # or |, The corresponding digits are 0, As a result, the number is 0, Otherwise 1 print(4 << 1) # Shift left << Move one bit to the left , Equivalent to times 2 print(4 << 2) # Shift left << Move two digits to the left , Equivalent to times 4 print(4 >> 1) # Shift right << Move one bit to the right , Equivalent to divided by 2 print(4 >> 2) # Shift right << Move two digits to the right , Equivalent to divided by 4
Power operation > Multiplication and division > Addition and subtraction > Shift operation > Bitwise AND > Press bit or > Comparison operator >and>or>=
Arithmetic operator > An operation > Comparison operator > Boolean operator > Assignment operator
