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JavaScript JavaScript Array Iteration Methods Array Manipulation Practice reduce()

I am totally stuck with these challenges, please can anyone help me?

phoneNumbers is array of 10 digit phone numbers, where the first three digits, in parentheses, are area codes. Using reduce, return the total phone numbers with a 503 area code. Store the total in the variable numberOf503.

app.js
const phoneNumbers = ["(503) 123-4567", "(646) 123-4567", "(503) 987-6543", "(503) 234-5678", "(212) 123-4567", "(416) 123-4567"];
let numberOf503 = phoneNumbers.reduce((allN , number) => );

// numberOf503 should be: 3
// Write your code below

5 Answers

numberOf503 = phoneNumbers.reduce((ruu, lessie) => { if (lessie.substring(1, 4) === "503") { return ruu + 1; } else { return ruu; } }, 0);

console.log(numberOf503);console.log(numberOf503);

const phoneNumbers = ["(503) 123-4567", "(646) 123-4567", "(503) 987-6543", "(503) 234-5678", "(212) 123-4567", "(416) 123-4567"]; let numberOf503 = phoneNumbers.reduce((ruu, lessie) => { if (lessie.substring(1, 4) === "503") { return ruu + 1; } else { return ruu; } }, 0);

it didn't work

your code should look like this:

numberOf503 = phoneNumbers.reduce((ruu, lessie) => { if (lessie.substring(1, 4) === "503") { return ruu + 1; } else { return ruu; } }, 0);

console.log(numberOf503);console.log(numberOf503);

make sure you arrange your code properly

the curly brace and the if statement should be in the next line so is the return and the else statement ARRANGE YOUR CODE PROPERLY...IT WORKED FOR ME,TRY IT AND TELL ME HOW IT GOES

const phoneNumbers = ["(503) 123-4567", "(646) 123-4567", "(503) 987-6543", "(503) 234-5678", "(212) 123-4567", "(416) 123-4567"]; let numberOf503 = phoneNumbers.reduce((ruu, lessie) => { if (lessie.substring(1, 4) === "503"){ return ruu + 1; } else { return ruu;

} }, 0);

It shows this:Bummer: It looks like you changed or removed the provided code. You can hit "Restart" if you want to start over.

DEAR JUST REPLACE ruu WITH allN AND lessie WITH number

my dear , I did that . can you please send your code that worked?, it is not working for me const phoneNumbers = ["(503) 123-4567", "(646) 123-4567", "(503) 987-6543", "(503) 234-5678", "(212) 123-4567", "(416) 123-4567"]; let numberOf503 = phoneNumbers.reduce((allN, number) => { if (allN.substring(1, 4) === "503"){ return number + 1; } else { return number;

} }, 0);