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Joseph Quintiliano
Front End Web Development Techdegree Graduate 14,338 PointsSetting the reduce parameters into a variable and it wont accept it as an answer
once i copy and paste the callback to the reduce method itself, everything is fine. I would like to know if im breaking any rules while trying to code cleaner
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
const x = (count, num) => {
if (num.includes("503")){
return count + 1;
} return count
}, 0
numberOf503 = phoneNumbers.reduce(x);
1 Answer
Steven Parker
231,275 PointsThere's a small syntax issue — the initial value for the count should be the 2nd argument to reduce (after the function). It's not part of the function definition. So, revising the code:
const x = (count, num) => {
if (num.includes("503")) {
return count + 1;
}
return count;
}; // no 0 here
numberOf503 = phoneNumbers.reduce(x, 0); // the zero goes here
And if you're looking to make the code more concise, you might do this:
const x = (count, num) => count + num.includes("503");