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

James Nunoo
James Nunoo
3,668 Points

not sure I understand this question on arrays

need a little help

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

function new(num){
for (var i = 100; i < temperatures.length i += 1){
  console.log(num);
 }
}
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

Hi James

No need for the function, you just need to loop through each of the array items getting the array index value.

Without a loop this would look something like this:

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

console.log(temperatures[0]);
console.log(temperatures[1]);
console.log(temperatures[2]);
console.log(temperatures[3]);
// etc

However, the question is to do that in a loop with either a for loop or while loop. This can be done by looping over the array length and console logging each iteration, like below:

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

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

Alternatively, using a while loop, it would look like this:

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

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

Notice that each of the examples i provide follow a similar pattern:

  1. a variable is set to iterate over i
  2. a conditional is made to check if the iteration variable is less that the array length i < temeratures.length
  3. After each console log, the iteration variable is incremented by 1 i++

Both of these loops are identical in there output and both do the exact same thing, but are syntactically different.

Hope this helps!

James Nunoo
James Nunoo
3,668 Points

Thank you Liam!