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Samuel Kleos
Front End Web Development Techdegree Student 11,860 PointsWhy doesn't parseInt(number).toString() work?
Here is my initial solution:
numberOf503 = phoneNumbers.reduce((acc, phone) => (parseInt(phone).toString().substring(0, 3) === "503")? acc+1 : acc, 0);
Here is the solution that worked
numberOf503 = phoneNumbers.reduce((acc, phone) => (phone.substring(1, 4) === "503") ? acc+1 : acc, 0);
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
Steven Parker
224,872 PointsSince all the phoneNumbers begin with a parenthesis, which is not a digit, then parseInt returns NaN.
That of course does not match "503".
Samuel Kleos
Front End Web Development Techdegree Student 11,860 PointsVery good to be aware of. Thank you. I will read docs for Built-in objects more carefully next time.
Rich Donnellan
Treehouse Moderator 25,868 PointsRich Donnellan
Treehouse Moderator 25,868 PointsI updated the question with code formatting hinting and fixed a typo in the title.