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

Posted by Tyrone Cartwright
Tyrone Cartwright
4,023 Points

Code took too long to run

My code took to long, is their something I'm doing wrong?

script.js 
var temperatures = [100,90,99,80,70,65,30,10];
    for (var i = 0; temperatures.length; i += 1) {
        console.log(temperatures[i]);
}
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

2 Answers

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

The conditional clause of this loop is simply "temperatures.length", which will be considered true because it is not zero. This causes the loop to run continuously.

Normally the conditional clause would contain a test that determines when the loop should continue. It's commonly done by comparing something to the loop variable, so you probably intended to write "i < temperatures.length".

Clayton Perszyk
MOD
Clayton Perszyk
Treehouse Moderator 48,850 Points
Clayton Perszyk
Clayton Perszyk
Treehouse Moderator 48,850 Points

check your exit clause. currently it will always evaluate to true, and as a result it is creating an infinite loop.