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JavaScript

Posted by RODRIGO MARTINEZ
RODRIGO MARTINEZ
5,912 Points

"Cannot read property 'filter' of null" error.

So my task is. Given an array of integers. Return an array, where the first element is the count of positives numbers and the second element is sum of negative numbers. If the input array is empty or null, return an empty array.

I get error "Cannot read property 'filter' of null"

My code :

function countPositivesSumNegatives(input) {
  let positiveNums = input.filter(number => number > 0);
  let negativeNums = input.filter(number => number < 0);

  let positiveCount = positiveNums.length;
  let negativeSum = negativeNums.reduce( (total, num) => {return total + num}  )

  let result = [positiveCount, negativeSum];


  return result;
}

1 Answer

Steven Parker
Steven Parker
243,134 Points
Steven Parker
Steven Parker
243,134 Points

The last part of the instructions reads "If the input array is empty or null, return an empty array." So it will be necessary to handle the possibility that "input" contains "null" before attempting to access the ".filter" method on it.

RODRIGO MARTINEZ
RODRIGO MARTINEZ
5,912 Points

Thanks a lot MR. Parker. Saved the day again. Solved. You are the real Team Tree house legend.