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# underestimatedCount

A value less than or equal to the number of elements in the sequence,
calculated nondestructively.

```
var underestimatedCount: Int { get }
```

## Discussion

The default implementation returns 0. If you provide your own
implementation, make sure to compute the value nondestructively.

> Complexity: O(1), except if the sequence also conforms to `Collection`.
> In this case, see the documentation of `Collection.underestimatedCount`.

---

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