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Total score comes out as NaN — JavaScript debugging challenge | BugHunt

javascriptNull / UndefinedMedium

Total score comes out as NaN

Time: 0:00

What it should do

sumScores(players) should add up every player's score, treating a player with no score as 0.

What goes wrong

As soon as one player is missing a score, the total becomes NaN instead of a number.

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Hints

This is a null and undefined errors bug

Cannot read properties of undefined, NoneType has no attribute, NaN appearing from nowhere.

Learn the null and undefined errors pattern