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JavaScript JavaScript Array Iteration Methods Array Manipulation Practice reduce()

Posted by Joseph Chauvin
.a{fill-rule:evenodd;}techdegree
Joseph Chauvin
Full Stack JavaScript Techdegree Student 12,029 Points

The correct result is stored in `numberOf503` but `reduce` was not used.

But I did use reduce()......

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 = 0;

phoneNumbers.reduce( (accum, phone) => {
  if (/(503)\w*/.test(phone)) {
    numberOf503 += 1;
    return numberOf503;
  }
    return numberOf503;
}, 0);

1 Answer

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,971 Points

I think it's referring to not assigning the return value of reduce to numberOf503, as in:

numberOf503 = phoneNumbers.reduce( (accum, phone) => {
  if (/(503)\w*/.test(phone)) {
    accum += 1;
    return accum;
  }
    return accum;
}, 0);
Joseph Chauvin
.a{fill-rule:evenodd;}techdegree
Joseph Chauvin
Full Stack JavaScript Techdegree Student 12,029 Points

Thank you!