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Reducer Sum
Section challenge · IntermediateJavaScript
Reward: +50 XP
PROBLEM

Reducer Sum

Write a function sumCloudAltitudes(clouds) that takes an array of cloud objects { name: string, altitude: number } and returns the sum of all their altitudes using the .reduce() method. If the array is empty, return 0.

Examples
sumCloudAltitudes([{ name: "cumulus", altitude: 3000 }, { name: "cirrus", altitude: 6000 }])
→ 9000
sumCloudAltitudes([])
→ 0
solution.js
JAVASCRIPT
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Tests

0 of 3 passing
  • •
    sum multiple heights
    sumCloudAltitudes([{ name: "cumulus", altitude: 3000 }, { name: "cirrus", altitude: 6000 }])
    expected 9000
  • •
    empty array → 0
    sumCloudAltitudes([])
    expected 0
  • •
    one cloud
    sumCloudAltitudes([{ name: "fog", altitude: 150 }])
    expected 150
On the line
+50 XP
Pass all 3 tests to claim it.