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JavaScript JavaScript Array Iteration Methods Array Manipulation Practice reduce()

Kathryn Crawford
Kathryn Crawford
5,515 Points
Posted by Kathryn Crawford
Kathryn Crawford
5,515 Points

Confused as to why my count isn't increasing

I'm using startsWith to find out which array items have (503) at the beginning of the phone numbers, but I'm thinking this is the wrong approach. For some reason, my count is not increasing using this method.

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
numberof503 = phoneNumbers.reduce( (count, number) => {
  if(number.startsWith('(503)')) {
    return count + 1;
  } 
  return count;
}, 0);

1 Answer

Adam N
Adam N
70,227 Points

Made a quick video about what's wrong: https://www.loom.com/share/839bda4741b74d168cfdaceb27937408?sharedAppSource=personal_library

Let me know if this helps!

Kathryn Crawford
Kathryn Crawford
5,515 Points
Kathryn Crawford
Kathryn Crawford
5,515 Points

Oh my goodness. Thanks for being my rubber duck!

Adam N
Adam N
70,227 Points

np haha! You can mark this question as solved by selecting a "best answer". :+1: