In Python, conditional statements are used to execute different blocks of code based on whether a certain condition evaluates to `True` or `False`. The basic structure includes `if`, `elif` (short for “else if”), and `else`.
Here's a basic syntax example:
x = 10
if x > 10:
print("x is greater than 10")
elif x == 10:
print("x is equal to 10")
else:
print("x is less than 10")
In this example:
- The `if` statement checks if `x` is greater than 10. If it's true, it executes the corresponding block of code. - The `elif` statement checks if `x` is equal to 10. If the previous condition (`x > 10`) was false and this condition is true, it executes the corresponding block of code. - The `else` statement catches anything that didn't satisfy the previous conditions and executes its corresponding block of code. It doesn't have a condition because it's the “catch-all” block.
You can have multiple `elif` statements, and `else` is optional.
Here's another example with multiple conditions:
x = 5
if x > 10:
print("x is greater than 10")
elif x == 10:
print("x is equal to 10")
elif x > 5:
print("x is greater than 5")
else:
print("x is 5 or less")
In this case, since `x` is less than 10, it moves to the next condition and checks if `x` is equal to 10. Since it's not, it moves to the next condition and checks if `x` is greater than 5, which is false. Therefore, the `else` block is executed.