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Won't the loop run 9 times, not 10?

var counter = 0; while ( counter < 10 ) { console.log(counter); counter += 1; } Won't the loop run 9 times, not 10? Because 10 can't be greater than 10.

2 Answers

This is something you're going to have to get used to--hehe. Zero is something and therefore counts as the first run!

counter = 0; // run once
counter = 1; // run twice
counter = 9; // run for the tenth time
counter = 10; // do not run for the 11th time


It is common to trace one's code to see how it is running. Try writing the same thing but console.log(counter) and then you can see the value of counter each time it iterates through the loop. If you get used to this and doing it to small subsets of numbers and then generalize the solution to a bigger set, it is much easier to see how the code is working.


O great, thanks.