Data type conversion

Function format describe The sample
int(x) Conversions include String and other numeric types int(“1”)
float(x) You can convert strings to other numeric types, and fill in any missing digits with zeros. For example, 1 becomes 1.0 The float (1) or float (” 1 “)
str(x) Convert numbers to strings str(1)
bool(x) Anything that is not zero is true. Anything but zero is true bool(0)

statement

  • Only when the conditions are met will it be executed. If the condition is not met, it will not be executed.
ifCondition: Something to doCopy the code
  • Case 1
age = 20
if age > 18:
    print("You can go to Internet cafes.")# Obviously this condition is met
Copy the code

Results of the above code:

  • Input by keyboard
age = int(input("Please enter your age"))# Since input() is of type STR, it can be used as an int.
if age > 18:
    print("You can go to Internet cafes.")
Copy the code

Results of the above code:

  • Else statements are antithetical to if statements
age = int(input("Please enter your age"))# Since input() is of type STR, it can be used as an int.
if age > 18:
    print("You can go to Internet cafes.")
else:
    print("I can only do my homework at home.")
Copy the code
  • Depending on the input value, different effects will be printed:

Elif statements and logical operators

  • When xxx1 is satisfied, thing 1 is executed, and then the whole if ends
  • When xxx1 is not satisfied, then judge xxx2, if xxx2 is satisfied, then do thing 2, and then the whole if ends
  • If xxx1 is not satisfied, xxx2 is not satisfied, if xxx3 is satisfied, then thing 3 is executed, and the whole if ends
age = int(input("Please enter your age"))
if age > 1 and age <= 7:#and Both conditions need to be met
    print("Childhood")
elif age > 7 and age <= 18:
    print("Young")
elif age > 18 and age <= 25:
    print("Youth")
else:
    print("Beyond five.")
Copy the code

Results of the above code:

If the nested

  • There’s a judgment statement inside a judgment statement
age = int(input("Please enter your age"))# convert the input string to an int
if age > 18:
    sex = input("Please enter gender")
    if sex == "Male":# check whether statements are nested
        print("You're old enough to move bricks.")
    elif sex == "Female":
        print("You can dress up pretty.")
    else:
        print("The third creature.")
Copy the code

Results of the above code:

Mora game

  • The computer randomly generates rock, paper, scissors for each game
  • Users enter rock, scissors, and paper for each office
  • Determine whether the user wins or the computer wins by judging the statement
"' 1-2-2 scissors stone 1 means" rock represents scissors 3 - cloth and cloth player wins: 1-2-2 3 3-1 ' ' '
import random # Make use of random modules
player = int(input("Please enter 1, rock 2, scissors 3, paper"))
pc = random.randint(1.3)# Select a random number between 1 and 3
if player < 4 and player > 0:# The following code belongs to if nesting
    if (player == 1 and pc == 2) or (player == 2 and pc ==3) or (player == 3 and pc == 1):
        print("The player wins")
    elif player == pc:
        print("Draw")
    else:
        print("Computer wins")
else:
    print("Invalid input")
Copy the code

Results of the above code: