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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Iterating through an Array

Sun Min
Sun Min
2,941 Points

Use a for or while loop to iterate through the values in the temperatures array from the first item -- 100 -- to the las

I see many of discussion on this challenge.

var temperatures = [100,90,99,80,70,65,30,10];

for (var i = 0; i < temperatures.length; i++) { console.log(temperatures[i]); }

in the for loop why many of answers with i ++ ? not i += 1?

var temperatures = [100,90,99,80,70,65,30,10];
for (var = i; i<temperatures.length; i+=1) {

<!DOCTYPE html>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
<script src="script.js"></script>

1 Answer

Rick Buffington
Rick Buffington
8,146 Points

You can use either one in a for loop and it will produce the same results - try it. It's a matter of semantics. If you were using these 2 items OUTSIDE of a for loop, the results would be different. i++ would be considered a Post Increment and ++i is called a Pre Increment ie:

var i = 1;
var j = i++; // j = 1 because the increment happend AFTER j was assigned to i
var i = 1;
var j = ++i; // j = 2 because the increment happened BEFORE j was assigned to i - this is the same as j+=i;

And also just a tidbit of info: i += 1 is the same as ++i.