Be concise.
Be useful.
All contributions dictatorially edited by webmasters to match personal tastes.
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Please try to avoid dependencies to third-party libraries and frameworks.
int n (x.size());final aSet = Set();
// omitted: add elements to aSet
final n = aSet.length;n := len(x)let n = x.sizeint n = x.size();n = len(x)n = x.size