forked from gitea/gitea
1
0
Fork 0
gitea/vendor/github.com/RoaringBitmap/roaring/setutil.go

551 lines
8.2 KiB
Go
Raw Normal View History

2018-05-19 20:49:46 +08:00
package roaring
func equal(a, b []uint16) bool {
if len(a) != len(b) {
return false
}
for i := range a {
if a[i] != b[i] {
return false
}
}
return true
}
func difference(set1 []uint16, set2 []uint16, buffer []uint16) int {
if 0 == len(set2) {
buffer = buffer[:len(set1)]
2018-05-19 20:49:46 +08:00
for k := 0; k < len(set1); k++ {
buffer[k] = set1[k]
}
return len(set1)
}
if 0 == len(set1) {
return 0
}
pos := 0
k1 := 0
k2 := 0
buffer = buffer[:cap(buffer)]
s1 := set1[k1]
s2 := set2[k2]
for {
if s1 < s2 {
buffer[pos] = s1
pos++
k1++
if k1 >= len(set1) {
break
}
s1 = set1[k1]
} else if s1 == s2 {
k1++
k2++
if k1 >= len(set1) {
break
}
s1 = set1[k1]
if k2 >= len(set2) {
for ; k1 < len(set1); k1++ {
buffer[pos] = set1[k1]
pos++
}
break
}
s2 = set2[k2]
} else { // if (val1>val2)
k2++
if k2 >= len(set2) {
for ; k1 < len(set1); k1++ {
buffer[pos] = set1[k1]
pos++
}
break
}
s2 = set2[k2]
}
}
return pos
}
func exclusiveUnion2by2(set1 []uint16, set2 []uint16, buffer []uint16) int {
if 0 == len(set2) {
buffer = buffer[:len(set1)]
copy(buffer, set1[:])
return len(set1)
}
if 0 == len(set1) {
buffer = buffer[:len(set2)]
copy(buffer, set2[:])
return len(set2)
}
pos := 0
k1 := 0
k2 := 0
s1 := set1[k1]
s2 := set2[k2]
buffer = buffer[:cap(buffer)]
for {
if s1 < s2 {
buffer[pos] = s1
pos++
k1++
if k1 >= len(set1) {
for ; k2 < len(set2); k2++ {
buffer[pos] = set2[k2]
pos++
}
break
}
s1 = set1[k1]
} else if s1 == s2 {
k1++
k2++
if k1 >= len(set1) {
for ; k2 < len(set2); k2++ {
buffer[pos] = set2[k2]
pos++
}
break
}
if k2 >= len(set2) {
for ; k1 < len(set1); k1++ {
buffer[pos] = set1[k1]
pos++
}
break
}
s1 = set1[k1]
s2 = set2[k2]
} else { // if (val1>val2)
buffer[pos] = s2
pos++
k2++
if k2 >= len(set2) {
for ; k1 < len(set1); k1++ {
buffer[pos] = set1[k1]
pos++
}
break
}
s2 = set2[k2]
}
}
return pos
}
func union2by2Cardinality(set1 []uint16, set2 []uint16) int {
pos := 0
k1 := 0
k2 := 0
if 0 == len(set2) {
return len(set1)
}
if 0 == len(set1) {
return len(set2)
}
s1 := set1[k1]
s2 := set2[k2]
for {
if s1 < s2 {
pos++
k1++
if k1 >= len(set1) {
pos += len(set2) - k2
break
}
s1 = set1[k1]
} else if s1 == s2 {
pos++
k1++
k2++
if k1 >= len(set1) {
pos += len(set2) - k2
break
}
if k2 >= len(set2) {
pos += len(set1) - k1
break
}
s1 = set1[k1]
s2 = set2[k2]
} else { // if (set1[k1]>set2[k2])
pos++
k2++
if k2 >= len(set2) {
pos += len(set1) - k1
break
}
s2 = set2[k2]
}
}
return pos
}
func intersection2by2(
set1 []uint16,
set2 []uint16,
buffer []uint16) int {
if len(set1)*64 < len(set2) {
return onesidedgallopingintersect2by2(set1, set2, buffer)
} else if len(set2)*64 < len(set1) {
return onesidedgallopingintersect2by2(set2, set1, buffer)
} else {
return localintersect2by2(set1, set2, buffer)
}
}
func intersection2by2Cardinality(
set1 []uint16,
set2 []uint16) int {
if len(set1)*64 < len(set2) {
return onesidedgallopingintersect2by2Cardinality(set1, set2)
} else if len(set2)*64 < len(set1) {
return onesidedgallopingintersect2by2Cardinality(set2, set1)
} else {
return localintersect2by2Cardinality(set1, set2)
}
}
func intersects2by2(
set1 []uint16,
set2 []uint16) bool {
// could be optimized if one set is much larger than the other one
if (0 == len(set1)) || (0 == len(set2)) {
return false
}
k1 := 0
k2 := 0
s1 := set1[k1]
s2 := set2[k2]
mainwhile:
for {
if s2 < s1 {
for {
k2++
if k2 == len(set2) {
break mainwhile
}
s2 = set2[k2]
if s2 >= s1 {
break
}
}
}
if s1 < s2 {
for {
k1++
if k1 == len(set1) {
break mainwhile
}
s1 = set1[k1]
if s1 >= s2 {
break
}
}
} else {
// (set2[k2] == set1[k1])
return true
}
}
return false
}
func localintersect2by2(
set1 []uint16,
set2 []uint16,
buffer []uint16) int {
if (0 == len(set1)) || (0 == len(set2)) {
return 0
}
k1 := 0
k2 := 0
pos := 0
buffer = buffer[:cap(buffer)]
s1 := set1[k1]
s2 := set2[k2]
mainwhile:
for {
if s2 < s1 {
for {
k2++
if k2 == len(set2) {
break mainwhile
}
s2 = set2[k2]
if s2 >= s1 {
break
}
}
}
if s1 < s2 {
for {
k1++
if k1 == len(set1) {
break mainwhile
}
s1 = set1[k1]
if s1 >= s2 {
break
}
}
} else {
// (set2[k2] == set1[k1])
buffer[pos] = s1
pos++
k1++
if k1 == len(set1) {
break
}
s1 = set1[k1]
k2++
if k2 == len(set2) {
break
}
s2 = set2[k2]
}
}
return pos
}
func localintersect2by2Cardinality(
set1 []uint16,
set2 []uint16) int {
if (0 == len(set1)) || (0 == len(set2)) {
return 0
}
k1 := 0
k2 := 0
pos := 0
s1 := set1[k1]
s2 := set2[k2]
mainwhile:
for {
if s2 < s1 {
for {
k2++
if k2 == len(set2) {
break mainwhile
}
s2 = set2[k2]
if s2 >= s1 {
break
}
}
}
if s1 < s2 {
for {
k1++
if k1 == len(set1) {
break mainwhile
}
s1 = set1[k1]
if s1 >= s2 {
break
}
}
} else {
// (set2[k2] == set1[k1])
pos++
k1++
if k1 == len(set1) {
break
}
s1 = set1[k1]
k2++
if k2 == len(set2) {
break
}
s2 = set2[k2]
}
}
return pos
}
func advanceUntil(
array []uint16,
pos int,
length int,
min uint16) int {
lower := pos + 1
if lower >= length || array[lower] >= min {
return lower
}
spansize := 1
for lower+spansize < length && array[lower+spansize] < min {
spansize *= 2
}
var upper int
if lower+spansize < length {
upper = lower + spansize
} else {
upper = length - 1
}
if array[upper] == min {
return upper
}
if array[upper] < min {
// means
// array
// has no
// item
// >= min
// pos = array.length;
return length
}
// we know that the next-smallest span was too small
lower += (spansize >> 1)
mid := 0
for lower+1 != upper {
mid = (lower + upper) >> 1
if array[mid] == min {
return mid
} else if array[mid] < min {
lower = mid
} else {
upper = mid
}
}
return upper
}
func onesidedgallopingintersect2by2(
smallset []uint16,
largeset []uint16,
buffer []uint16) int {
if 0 == len(smallset) {
return 0
}
buffer = buffer[:cap(buffer)]
k1 := 0
k2 := 0
pos := 0
s1 := largeset[k1]
s2 := smallset[k2]
mainwhile:
for {
if s1 < s2 {
k1 = advanceUntil(largeset, k1, len(largeset), s2)
if k1 == len(largeset) {
break mainwhile
}
s1 = largeset[k1]
}
if s2 < s1 {
k2++
if k2 == len(smallset) {
break mainwhile
}
s2 = smallset[k2]
} else {
buffer[pos] = s2
pos++
k2++
if k2 == len(smallset) {
break
}
s2 = smallset[k2]
k1 = advanceUntil(largeset, k1, len(largeset), s2)
if k1 == len(largeset) {
break mainwhile
}
s1 = largeset[k1]
}
}
return pos
}
func onesidedgallopingintersect2by2Cardinality(
smallset []uint16,
largeset []uint16) int {
if 0 == len(smallset) {
return 0
}
k1 := 0
k2 := 0
pos := 0
s1 := largeset[k1]
s2 := smallset[k2]
mainwhile:
for {
if s1 < s2 {
k1 = advanceUntil(largeset, k1, len(largeset), s2)
if k1 == len(largeset) {
break mainwhile
}
s1 = largeset[k1]
}
if s2 < s1 {
k2++
if k2 == len(smallset) {
break mainwhile
}
s2 = smallset[k2]
} else {
pos++
k2++
if k2 == len(smallset) {
break
}
s2 = smallset[k2]
k1 = advanceUntil(largeset, k1, len(largeset), s2)
if k1 == len(largeset) {
break mainwhile
}
s1 = largeset[k1]
}
}
return pos
}
func binarySearch(array []uint16, ikey uint16) int {
low := 0
high := len(array) - 1
for low+16 <= high {
middleIndex := int(uint32(low+high) >> 1)
middleValue := array[middleIndex]
if middleValue < ikey {
low = middleIndex + 1
} else if middleValue > ikey {
high = middleIndex - 1
} else {
return middleIndex
}
}
for ; low <= high; low++ {
val := array[low]
if val >= ikey {
if val == ikey {
return low
}
break
}
}
return -(low + 1)
}