# Tests failed to run due to an error: "". Check your code and try again

Hello Im trying to resolve Maximize Stock Trading Profit challange and I keep having the same issue Tests failed to run due to an error: “”. Check your code and try again.. Im totally stucked.

Given the daily values of a stock, create a function called `maxProfitDays()` that, given a list of integers, will return the index value of the two elements that represent the day on which one should have bought a share and the day on which one should have sold a share based on the max profit.

A list of integers will represent the stock price at the beginning or “opening bell” of each day for a week. You are required to buy and sell only once. You also must buy a stock before selling it.

For example, given the list `[17, 11, 60, 25, 150, 75, 31, 120]`, you can assume that index 0 represents day 0 and index 7 represents day 7. In this case, purchasing on day 1 and selling on day 4 would yield the most profit. If we were to call `maxProfitDays([17, 11, 60, 25, 150, 75, 31, 120])`, the function would return `[1, 4]`.

function maxProfitDays (profitDays) { let profit = 0; let index = 0; for (let i= 0; i<profitDays.length; i++) { for (let j=i; j<profitDays.length; j++) { if (profitDays[j]-profitDays[i]>profit) { profit = profitDays[j]-profitDays[i]; index = [i , j] } } } return console.log (index) } const list = [17, 11, 60, 25, 150, 75, 31, 120] maxProfitDays(list)

`console.log` does not return anything, it just makes stuff print out to the console/screen.
so
`return console.log (index)`
should be
`return index`
or
`console.log (index)`
`return index`

Note that sometimes there are problems with the tests for the challenges if there are any `console.log` in the code.

Yes it was my first option, I tried many ways, always the same error

Based on the image you just posted, you appear to have removed the code that performs the test. Put this line back in:

``````// Leave this so we can test your code:
module.exports = maxProfitDays;
``````

and correct the returning of the index variable as @janbazant1107978602 indicated and you should be fine.

Oh I missed that detail thank youuuuuuuu so much!

mega, this code challenge works for you now?

I’m getting the same error. I did this off-platform and it works just fine but it isn’t running for me in the codecademy environment. Even if I just replace all my code with a `console.log('Hello World');` nothing prints to the console and the tests can’t be run. I did not delete the export of the function, so that’s not the issue.

Other code challenges seem to work fine.