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JavaScript JavaScript Array Iteration Methods Array Manipulation Practice reduce()

Posted by saddam lashuel
saddam lashuel
Courses Plus Student 9,178 Points

JavaScript Array Iteration methods

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((acc, num)=>{ if(num.slice(1,4)== 503){ return acc + 1; }
},0);

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((acc, num)=>{
          if(num.slice(1,4)== 503){
              return acc + 1; }          
},0);

1 Answer

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

The callback function should still return something even if current number doesn't add to the count.

saddam lashuel
saddam lashuel
Courses Plus Student 9,178 Points

Thanks!!!!