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diff --git a/vendor/github.com/bits-and-blooms/bitset/README.md b/vendor/github.com/bits-and-blooms/bitset/README.md new file mode 100644 index 000000000..97e83071e --- /dev/null +++ b/vendor/github.com/bits-and-blooms/bitset/README.md @@ -0,0 +1,93 @@ +# bitset + +*Go language library to map between non-negative integers and boolean values* + +[](https://github.com/willf/bitset/actions?query=workflow%3ATest) +[](https://goreportcard.com/report/github.com/willf/bitset) +[](https://pkg.go.dev/github.com/bits-and-blooms/bitset?tab=doc) + + +## Description + +Package bitset implements bitsets, a mapping between non-negative integers and boolean values. +It should be more efficient than map[uint] bool. + +It provides methods for setting, clearing, flipping, and testing individual integers. + +But it also provides set intersection, union, difference, complement, and symmetric operations, as well as tests to check whether any, all, or no bits are set, and querying a bitset's current length and number of positive bits. + +BitSets are expanded to the size of the largest set bit; the memory allocation is approximately Max bits, where Max is the largest set bit. BitSets are never shrunk. On creation, a hint can be given for the number of bits that will be used. + +Many of the methods, including Set, Clear, and Flip, return a BitSet pointer, which allows for chaining. + +### Example use: + +```go +package main + +import ( + "fmt" + "math/rand" + + "github.com/bits-and-blooms/bitset" +) + +func main() { + fmt.Printf("Hello from BitSet!\n") + var b bitset.BitSet + // play some Go Fish + for i := 0; i < 100; i++ { + card1 := uint(rand.Intn(52)) + card2 := uint(rand.Intn(52)) + b.Set(card1) + if b.Test(card2) { + fmt.Println("Go Fish!") + } + b.Clear(card1) + } + + // Chaining + b.Set(10).Set(11) + + for i, e := b.NextSet(0); e; i, e = b.NextSet(i + 1) { + fmt.Println("The following bit is set:", i) + } + if b.Intersection(bitset.New(100).Set(10)).Count() == 1 { + fmt.Println("Intersection works.") + } else { + fmt.Println("Intersection doesn't work???") + } +} +``` + +As an alternative to BitSets, one should check out the 'big' package, which provides a (less set-theoretical) view of bitsets. + +Package documentation is at: https://pkg.go.dev/github.com/bits-and-blooms/bitset?tab=doc + +## Memory Usage + +The memory usage of a bitset using N bits is at least N/8 bytes. The number of bits in a bitset is at least as large as one plus the greatest bit index you have accessed. Thus it is possible to run out of memory while using a bitset. If you have lots of bits, you might prefer compressed bitsets, like the [Roaring bitmaps](http://roaringbitmap.org) and its [Go implementation](https://github.com/RoaringBitmap/roaring). + +## Implementation Note + +Go 1.9 introduced a native `math/bits` library. We provide backward compatibility to Go 1.7, which might be removed. + +It is possible that a later version will match the `math/bits` return signature for counts (which is `int`, rather than our library's `unit64`). If so, the version will be bumped. + +## Installation + +```bash +go get github.com/bits-and-blooms/bitset +``` + +## Contributing + +If you wish to contribute to this project, please branch and issue a pull request against master ("[GitHub Flow](https://guides.github.com/introduction/flow/)") + +## Running all tests + +Before committing the code, please check if it passes tests, has adequate coverage, etc. +```bash +go test +go test -cover +``` |