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Computer Science Algorithms: Sorting and Searching Sorting Algorithms Code for Selection Sort

Andrew Whatmore
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Andrew Whatmore
Full Stack JavaScript Techdegree Student 13,175 Points
Posted by Andrew Whatmore
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Andrew Whatmore
Full Stack JavaScript Techdegree Student 13,175 Points

[0] in JavaScript splice method

What is the [0] doing in the following line in the JavaScript version of the code? The code still seems to work without it. Thanks

sortedList.push(list.splice(indexToMove, 1)[0]);

1 Answer

Laura Coronel
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Laura Coronel
Treehouse Teacher
Laura Coronel
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Laura Coronel
Treehouse Teacher

Great question Andrew Whatmore! 😊 The [0] accesses the first (and only) item in the array returned by splice().

The splice() method returns an array of the items it removes from the original array. Since you're removing just one item, [0] gets that item itself rather than the array containing it.

Without [0], you'd be pushing an array into sortedList instead of the individual item. The code might still run, but the resulting array would have a different structure.