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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
231,261 Points
Steven Parker
Steven Parker
231,261 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