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Ceil-Ian Maralit
Front End Web Development Techdegree Graduate 19,434 Pointsreduce problems
I don't really know how to access those values in an array, what I only know is how to access it individually, which is a problem to me now. Would someone please elaborate it to me? It would be much appreciated. Thank you!!
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
1 Answer
hombah
Python Web Development Techdegree Student 16,241 PointsI think there are many ways to complete this challenge, reduce can also be a bit confusing to understand. We need to set a sum variable which we start at 0 and then loop through the tel number array. if we get a tel number that starts with 503 we increase the sum by 1, in the end we return the sum. Its a useful helper function for going through a lot of data in an array and keeping tally of something or returning a sum ect
const phoneNumbers = ["(503) 123-4567", "(646) 123-4567", "(503) 987-6543", "(503) 234-5678", "(212) 123-4567", "(416) 123-4567"];
let numberOf503;
numberOf503 = phoneNumbers.reduce((total, telNumberString) => {
if (telNumberString.slice(1, 4) === "503") {
total++;
}
return total;
}, 0);
// numberOf503 should be: 3
// Write your code below
Ceil-Ian Maralit
Front End Web Development Techdegree Graduate 19,434 PointsCeil-Ian Maralit
Front End Web Development Techdegree Graduate 19,434 PointsOh thank you so much for explaining it to me. I actually solved it after you showed me the slice method earlier. Yes, it's a bit confusing at first, I agree. Thanks a lot!