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How to Swap the Contents of Two Variables in Python
Here is the problem:
We have two variables, glass1
and glass2
. glass1
contains milk, and glass2
contains juice. Write three lines of code to switch the contents of these variables. You are only allowed to use variables to solve this problem.
Hint: Imagine you have a glass of milk and a glass of juice. How would you switch the liquids in real life?
More Hint:
If we have two physical glasses and we want to switch their contents, we would need an extra glass to temporarily hold the contents of one glass. Similarly, in programming, we can create a temporary variable to store the contents of one variable during the switch.
Step-by-Step Explanation of the Code:
temp = glass1
This temporary variable acts like the extra glass in real life, allowing us to swap the contents effectively.
By storing the contents of glass1
in the temp
variable, we free up glass1
to hold the contents of glass2
. This can be achieved with the following line of code:
glass1 = glass2
Now, glass1
contains what was originally in glass2
, and the contents of glass1
are still safely stored in the temp
variable.
Finally, we can place the contents of the temp
variable (which holds the original contents of glass1
) into glass2
using:
glass2 = temp
With these three steps, the contents of glass1
and glass2
are successfully swapped!
glass1 = "milk"
glass2 = "juice"
temp = glass1
glass1 = glass2
glass2 = temp
print(glass1)
print(glass2)