Lesson 5
Writing Reusable and Self-explanatory Programs
Chapter 2: Shortcut assignment statements
How to swap variables
Did you manage to complete the swapping exercise?
Now, you might have tried the following as the first attempt. And it does not work.
x
and y
are both 24
after swapping.
x = 15
y = 24
x = y
y = x
print(x)
print(y)
What happened here was that I have already updated x
to point to 24
in Line 3, and there is no longer a way for you to access the reference to 15
!
So, to be able to swap variables, you will need to introduce another variable to point to what x
is pointing (15
) first. Then you update x
to point to what y
is pointing to (24
), then update y
to point to what your temporary variable is pointing (15
).
x = 15
y = 24
temp = x
x = y
y = temp
print(x)
print(y)