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JavaScript JavaScript Array Iteration Methods Array Manipulation Practice reduce()

victor E
victor E
19,145 Points
Posted by victor E
victor E
19,145 Points

Using reduce

Not sure what I am missing, i have a feeling it has something to do with scope

app.js 
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((count, number) => {
    if(number[1] === '5') {
      return count + 1;
    }else return
}, 0);




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

1 Answer

Steven Parker
Steven Parker
231,184 Points
Steven Parker
Steven Parker
231,184 Points

There are no scope issues here. But when the count is not incremented, you still need to retain the count:

    } else return count;  // without "count" it returns "undefined"
victor E
victor E
19,145 Points
victor E
victor E
19,145 Points

That did the trick, thank you!