Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

JavaScript JavaScript Array Iteration Methods Array Manipulation Practice filter()

Jason Dsouza
Jason Dsouza
1,378 Points
Posted by Jason Dsouza
Jason Dsouza
1,378 Points

How can i solve this?

I need help to solve this Js problem

Link: https://teamtreehouse.com/library/javascript-array-iteration-methods/array-manipulation/practice-filter

app.js 
const years = [1989, 2015, 2000, 1999, 2013, 1973, 2012];
let century20;

// century20 should be: [1989, 2000, 1999, 1973]
// Write your code below

century20 = years.filter (year =>{
  if(year.charAt(0) !== 2){
    century20.push(year);
  }
});

1 Answer

Steven Parker
Steven Parker
231,236 Points
Steven Parker
Steven Parker
231,236 Points

The outer structure is good, but you a few issues with the filter function:

  • you don't need to "push" onto the output, "filter" will return a complete array to assign
  • "charAt" is a string function, but "years" is an array of numbers
  • the filter function must return a boolean comparison result
  • be sure the filter includes 2000, but nothing above