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

Zakk George
Zakk George
4,550 Points
Posted by Zakk George
Zakk George
4,550 Points

JS quiz stuck

I sort of get what its asking but I'm not exactly sure what Im doing wrong. Its telling me to iterate the array from 1st to last. ( aka .shift(); ) and then print out the result in the console ( console.log(temperatures); ). Confused as to what exactly its asking for.

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

for ( var i = 0; i < temperatures.length; i += 1) {
  temperatures.shift();
}

console.log(temperatures);
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

1 Answer

Florian Tönjes
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.a{fill-rule:evenodd;}techdegree seal-36
Florian Tönjes
Full Stack JavaScript Techdegree Graduate 50,856 Points
Florian Tönjes
.a{fill-rule:evenodd;}techdegree seal-36
Florian Tönjes
Full Stack JavaScript Techdegree Graduate 50,856 Points

Hey Zakk,

by using the 'shift' method you are removing an array item on each pass, which reduces the array's length. On the 4th pass the array only has 4 elements left, because 'i' is 4 and the 'i < temperatures.length' condition is no longer met, the loop breaks and doesn't log all the temperatures to the console.

You can access the array items directly without altering the array:

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

Regards, Florian

Zakk George
Zakk George
4,550 Points
Zakk George
Zakk George
4,550 Points

Ah I see. I was overthinking it. I had thought it wanted me to remove each element from the array one by one. Thanks!