73 lines
1.6 KiB
Go
73 lines
1.6 KiB
Go
package bytesutil
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import (
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"bytes"
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"sort"
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)
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// Sort sorts a slice of byte slices.
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func Sort(a [][]byte) {
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sort.Sort(byteSlices(a))
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}
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func IsSorted(a [][]byte) bool {
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return sort.IsSorted(byteSlices(a))
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}
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func SearchBytes(a [][]byte, x []byte) int {
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return sort.Search(len(a), func(i int) bool { return bytes.Compare(a[i], x) >= 0 })
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}
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// Union returns the union of a & b in sorted order.
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func Union(a, b [][]byte) [][]byte {
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n := len(b)
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if len(a) > len(b) {
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n = len(a)
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}
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other := make([][]byte, 0, n)
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for {
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if len(a) > 0 && len(b) > 0 {
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if cmp := bytes.Compare(a[0], b[0]); cmp == 0 {
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other, a, b = append(other, a[0]), a[1:], b[1:]
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} else if cmp == -1 {
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other, a = append(other, a[0]), a[1:]
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} else {
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other, b = append(other, b[0]), b[1:]
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}
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} else if len(a) > 0 {
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other, a = append(other, a[0]), a[1:]
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} else if len(b) > 0 {
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other, b = append(other, b[0]), b[1:]
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} else {
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return other
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}
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}
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}
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// Intersect returns the intersection of a & b in sorted order.
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func Intersect(a, b [][]byte) [][]byte {
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n := len(b)
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if len(a) > len(b) {
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n = len(a)
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}
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other := make([][]byte, 0, n)
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for len(a) > 0 && len(b) > 0 {
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if cmp := bytes.Compare(a[0], b[0]); cmp == 0 {
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other, a, b = append(other, a[0]), a[1:], b[1:]
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} else if cmp == -1 {
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a = a[1:]
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} else {
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b = b[1:]
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}
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}
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return other
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}
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type byteSlices [][]byte
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func (a byteSlices) Len() int { return len(a) }
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func (a byteSlices) Less(i, j int) bool { return bytes.Compare(a[i], a[j]) == -1 }
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func (a byteSlices) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
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