While Loop

For-loops are great for iterating over a fixed number of elements. But what if you don't know how many elements you need to iterate over? In this case, you can use a while-loop.

Syntax of a while loop:

while condition:
    # do something

The body of the while loop will be performed until condition is satisfied.

Let's see an example:

num = 1

while num < 10:
    print(num, end=' ')
    num += 1

Here, we start with the value of num be equal to 1. We first check that the value of num is less than or equal to 10. If this is true, we print the value of num and then increment it by 1 (notice +=). Thus, on the second iteration, the value of num will be 2. This process will continue until the value of num is 10. At this point, the condition num < 10 will be false and the while loop will terminate.

Therefore, the output should be the numbers from 1 to 9 (but not 10):

1 2 3 4 5 6 7 8 9