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JavaScript JavaScript Array Iteration Methods Array Manipulation Practice reduce()

Posted by zkb
.a{fill-rule:evenodd;}techdegree seal-36
zkb
Front End Web Development Techdegree Graduate 13,636 Points

Can somebody help me figure out what's wrong with my code?

It's telling me "unexpected token ." Well I have absolutely no idea where I went wrong here. I'd appreciate any help to get past this. Thank you.

app.js 
const phoneNumbers = ["(503) 123-4567", "(646) 123-4567", "(503) 987-6543", "(503) 234-5678", "(212) 123-4567", "(416) 123-4567"];
let numberOf503;

// numberOf503 should be: 3
// Write your code below
let numberOf503 = phoneNumbers.reduce(count, number) => {
  if(number.includes('(503)')) {
    count += 1;
  }
  return count;
}, 0;

1 Answer

Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

You're close, but there are 2 issues:

  • a variable can only declared once, so remove the "let" from line 6
  • the "reduce" method is missing parentheses around its arguments (lines 6 and 11)
zkb
.a{fill-rule:evenodd;}techdegree seal-36
zkb
Front End Web Development Techdegree Graduate 13,636 Points

I passed it, thank you!