#Python's condition statement

When writing programs, we often need to execute different codes according to different situations. For example, in a weather application, if the weather is sunny, it will display "Remember to wear sunglasses when going out"; if it is raining, it will display "Remember to bring an umbrella when going out." This behavior of executing different codes according to conditions is called conditional control.

#Syntax

Python uses if, elif and else to perform conditional judgment. Its basic syntax is as follows:

if condition-1:       # If condition-1 is True, then execute code-block-1
    code-block-1
elif condition-2:     # Otherwise (i.e. condition-1 is False), if condition-2 is True, then execute code-block-2
    code-block-2

...

elif condition-n:     # Otherwise (i.e. all previous conditions are False), if condition-n is True, execute code-block-n
    code-block-n
else:                 # Otherwise (i.e. all previous conditions are False), execute code block n+1
    code-block-n+1

For example:

SUNNY:int = 1
RAINY:int = 2

weather:int = SUNNY

if weather == SUNNY:
    print("Remember to wear sunglasses when going out")
elif weather == RAINY:
    print("Remember to bring an umbrella when you go out")
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#Code block

Python code blocks are separated by indentation, for example:

print("This is the outermost code block")                                   # Block A
if True:
    print("This is the code block of the outer if condition")               # Block B
    if False:
        print("This is the code block of the inner if condition")           # Block C
        print("This is the code block of the inner if condition")           # Block C
    print("This is the code block of the outer if condition")               # Block B
print("This is the outermost code block")                                   # Block A
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There is no specific rule for indentation, but four spaces is usually used.

#Conditional expression

In programming, we often encounter some simple conditional judgments, such as "go buy fruit, if there are pineapples, buy two, if not, buy a watermelon".
In some other programming languages, you can use the ternary operator to simplify the operation, such as pineapple_exists ? 2 : 1 (if pineapple_exists is True, the result is 2, otherwise the result is 1).
There is no ternary operator in Python, you can use if-else to implement this function:

pineapple_exists:bool = True
count:int = 2 if pineapple_exists else 1   # The result is 2 if pineapple_exists is True, otherwise it is 1
print(count)
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#Practise

Please implement the function to determine whether an integer is even or odd, and get the input through input.

• Integers that are divisible by 2 are even numbers, and integers that are not divisible by 2 are odd numbers.

number:int = int(input("Please enter an integer:"))

if True:  # Modify the code here to determine whether number is even or odd
    print(number, "is an even number")
else:
    print(number, "is an odd number")
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