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JavaScript JavaScript Array Iteration Methods Array Manipulation Practice reduce()

Posted by Khumoyunmirzo Nosirov
Khumoyunmirzo Nosirov
8,689 Points

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

Lester Rumbidzayi Tsuro
Lester Rumbidzayi Tsuro
15,397 Points
Lester Rumbidzayi Tsuro
Lester Rumbidzayi Tsuro
15,397 Points

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

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

Khumoyunmirzo Nosirov
Khumoyunmirzo Nosirov
8,689 Points

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

Lester Rumbidzayi Tsuro
Lester Rumbidzayi Tsuro
15,397 Points
Lester Rumbidzayi Tsuro
Lester Rumbidzayi Tsuro
15,397 Points

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

Lester Rumbidzayi Tsuro
Lester Rumbidzayi Tsuro
15,397 Points

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

Khumoyunmirzo Nosirov
Khumoyunmirzo Nosirov
8,689 Points
Khumoyunmirzo Nosirov
Khumoyunmirzo Nosirov
8,689 Points

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);

Khumoyunmirzo Nosirov
Khumoyunmirzo Nosirov
8,689 Points

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

Lester Rumbidzayi Tsuro
Lester Rumbidzayi Tsuro
15,397 Points
Lester Rumbidzayi Tsuro
Lester Rumbidzayi Tsuro
15,397 Points

DEAR JUST REPLACE ruu WITH allN AND lessie WITH number

Khumoyunmirzo Nosirov
Khumoyunmirzo Nosirov
8,689 Points
Khumoyunmirzo Nosirov
Khumoyunmirzo Nosirov
8,689 Points

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);