use vec::{len, push};
use core::cmp::{Eq, Ord};
+use dvec::DVec;
export le;
export merge_sort;
fn qsort(self) { quick_sort3(self); }
}
+const MIN_MERGE: uint = 64;
+const MIN_GALLOP: uint = 7;
+const INITIAL_TMP_STORAGE: uint = 128;
+
+fn timsort<T: Ord>(array: &[mut T]) {
+ let size = array.len();
+ if size < 2 {
+ return;
+ }
+
+ if size < MIN_MERGE {
+ let initRunLen = countRunAndMakeAscending(array);
+ binarysort(array, initRunLen);
+ return;
+ }
+
+ let ms = &MergeState();
+ let minRun = minRunLength(size);
+
+ let mut idx = 0;
+ let mut remaining = size;
+ loop {
+ let arr = vec::mut_view(array, idx, size);
+ let mut runLen: uint = countRunAndMakeAscending(arr);
+
+ if runLen < minRun {
+ let force = if remaining <= minRun {remaining} else {minRun};
+ let slice = vec::mut_view(arr, 0, force);
+ binarysort(slice, runLen);
+ runLen = force;
+ }
+
+ ms.pushRun(idx, runLen);
+ ms.mergeCollapse(array);
+
+ idx += runLen;
+ remaining -= runLen;
+ if remaining == 0 { break; }
+ }
+
+ ms.mergeForceCollapse(array);
+}
+
+fn binarysort<T: Ord>(array: &[mut T], start: uint) {
+ let size = array.len();
+ let mut start = start;
+ assert start <= size;
+
+ if start == 0 { start += 1; }
+
+ let mut pivot = ~[mut];
+ vec::reserve(pivot, 1);
+ unsafe { vec::raw::set_len(pivot, 1); };
+
+ while start < size {
+ unsafe {
+ let tmpView = vec::mut_view(array, start, start+1);
+ vec::raw::memmove(pivot, tmpView, 1);
+ }
+ let mut left = 0;
+ let mut right = start;
+ assert left <= right;
+
+ while left < right {
+ let mid = (left + right) >> 1;
+ if pivot[0] < array[mid] {
+ right = mid;
+ } else {
+ left = mid+1;
+ }
+ }
+ assert left == right;
+ let mut n = start-left;
+
+ unsafe {
+ moveVec(array, left+1, array, left, n);
+ }
+ array[left] <-> pivot[0];
+ start += 1;
+ }
+ unsafe { vec::raw::set_len(pivot, 0); } // Forget the boxed element
+}
+
+/// Reverse the order of elements in a slice, in place
+fn reverseSlice<T>(v: &[mut T], start: uint, end:uint) {
+ let mut i = start;
+ while i < end / 2 {
+ v[i] <-> v[end - i - 1];
+ i += 1;
+ }
+}
+
+pure fn minRunLength(n: uint) -> uint {
+ let mut n = n;
+ let mut r = 0; // becomes 1 if any 1 bits are shifted off
+
+ while n >= MIN_MERGE {
+ r |= n & 1;
+ n >>= 1;
+ }
+ return n + r;
+}
+
+fn countRunAndMakeAscending<T: Ord>(array: &[mut T]) -> uint {
+ let size = array.len();
+ assert size > 0;
+ if size == 1 { return 1; }
+
+ let mut run = 2;
+ if array[1] < array[0] {
+ while run < size && array[run] < array[run-1] {
+ run += 1;
+ }
+ reverseSlice(array, 0, run);
+ } else {
+ while run < size && array[run] >= array[run-1] {
+ run += 1;
+ }
+ }
+
+ return run;
+}
+
+pure fn gallopLeft<T: Ord>(key: &const T, array: &[const T], hint: uint) -> uint {
+ let size = array.len();
+ assert size != 0 && hint < size;
+
+ let mut lastOfs = 0;
+ let mut ofs = 1;
+
+ if *key > array[hint] {
+ // Gallop right until array[hint+lastOfs] < key <= array[hint+ofs]
+ let maxOfs = size - hint;
+ while ofs < maxOfs && *key > array[hint+ofs] {
+ lastOfs = ofs;
+ ofs = (ofs << 1) + 1;
+ if ofs < lastOfs { ofs = maxOfs; } // uint overflow guard
+ }
+ if ofs > maxOfs { ofs = maxOfs; }
+
+ lastOfs += hint;
+ ofs += hint;
+ } else {
+ let maxOfs = hint + 1;
+ while ofs < maxOfs && *key <= array[hint-ofs] {
+ lastOfs = ofs;
+ ofs = (ofs << 1) + 1;
+ if ofs < lastOfs { ofs = maxOfs; } // uint overflow guard
+ }
+
+ if ofs > maxOfs { ofs = maxOfs; }
+
+ let tmp = lastOfs;
+ lastOfs = hint - ofs;
+ ofs = hint - tmp;
+ }
+ assert (lastOfs < ofs || lastOfs+1 < ofs+1) && ofs <= size;
+
+ lastOfs += 1;
+ while lastOfs < ofs {
+ let m = lastOfs + ((ofs - lastOfs) >> 1);
+ if *key > array[m] {
+ lastOfs = m+1;
+ } else {
+ ofs = m;
+ }
+ }
+ assert lastOfs == ofs;
+ return ofs;
+}
+
+pure fn gallopRight<T: Ord>(key: &const T, array: &[const T], hint: uint) -> uint {
+ let size = array.len();
+ assert size != 0 && hint < size;
+
+ let mut lastOfs = 0;
+ let mut ofs = 1;
+
+ if *key >= array[hint] {
+ // Gallop right until array[hint+lastOfs] <= key < array[hint+ofs]
+ let maxOfs = size - hint;
+ while ofs < maxOfs && *key >= array[hint+ofs] {
+ lastOfs = ofs;
+ ofs = (ofs << 1) + 1;
+ if ofs < lastOfs { ofs = maxOfs; }
+ }
+ if ofs > maxOfs { ofs = maxOfs; }
+
+ lastOfs += hint;
+ ofs += hint;
+ } else {
+ // Gallop left until array[hint-ofs] <= key < array[hint-lastOfs]
+ let maxOfs = hint + 1;
+ while ofs < maxOfs && *key < array[hint-ofs] {
+ lastOfs = ofs;
+ ofs = (ofs << 1) + 1;
+ if ofs < lastOfs { ofs = maxOfs; }
+ }
+ if ofs > maxOfs { ofs = maxOfs; }
+
+ let tmp = lastOfs;
+ lastOfs = hint - ofs;
+ ofs = hint - tmp;
+ }
+
+ assert (lastOfs < ofs || lastOfs+1 < ofs+1) && ofs <= size;
+
+ lastOfs += 1;
+ while lastOfs < ofs {
+ let m = lastOfs + ((ofs - lastOfs) >> 1);
+
+ if *key >= array[m] {
+ lastOfs = m + 1;
+ } else {
+ ofs = m;
+ }
+ }
+ assert lastOfs == ofs;
+ return ofs;
+}
+
+struct RunState {
+ base: uint,
+ len: uint,
+}
+
+struct MergeState<T> {
+ mut minGallop: uint,
+ mut tmp: ~[T],
+ runs: DVec<RunState>,
+
+ drop {
+ unsafe {
+ vec::raw::set_len(self.tmp, 0);
+ }
+ }
+}
+
+fn MergeState<T>() -> MergeState<T> {
+ let mut tmp = ~[];
+ vec::reserve(tmp, INITIAL_TMP_STORAGE);
+ MergeState {
+ minGallop: MIN_GALLOP,
+ tmp: tmp,
+ runs: DVec(),
+ }
+}
+
+impl<T: Ord> &MergeState<T> {
+ fn pushRun(runBase: uint, runLen: uint) {
+ let tmp = RunState{base: runBase, len: runLen};
+ self.runs.push(tmp);
+ }
+
+ fn mergeAt(n: uint, array: &[mut T]) {
+ let mut size = self.runs.len();
+ assert size >= 2;
+ assert n == size-2 || n == size-3;
+
+ do self.runs.borrow_mut |arr| {
+
+ let mut b1 = arr[n].base;
+ let mut l1 = arr[n].len;
+ let b2 = arr[n+1].base;
+ let l2 = arr[n+1].len;
+
+ assert l1 > 0 && l2 > 0;
+ assert b1 + l1 == b2;
+
+ arr[n].len = l1 + l2;
+ if n == size-3 {
+ arr[n+1].base = arr[n+2].base;
+ arr[n+1].len = arr[n+2].len;
+ }
+
+ let slice = vec::mut_view(array, b1, b1+l1);
+ let k = gallopRight(&const array[b2], slice, 0);
+ b1 += k;
+ l1 -= k;
+ if l1 != 0 {
+ let slice = vec::mut_view(array, b2, b2+l2);
+ let l2 = gallopLeft(
+ &const array[b1+l1-1],slice,l2-1);
+ if l2 > 0 {
+ if l1 <= l2 {
+ self.mergeLo(array, b1, l1, b2, l2);
+ } else {
+ self.mergeHi(array, b1, l1, b2, l2);
+ }
+ }
+ }
+ }
+ self.runs.pop();
+ }
+
+ fn mergeLo(array: &[mut T], base1: uint, len1: uint, base2: uint, len2: uint) {
+ assert len1 != 0 && len2 != 0 && base1+len1 == base2;
+
+ vec::reserve(self.tmp, len1);
+
+ unsafe {
+ vec::raw::set_len(self.tmp, len1);
+ moveVec(self.tmp, 0, array, base1, len1);
+ }
+
+ let mut c1 = 0;
+ let mut c2 = base2;
+ let mut dest = base1;
+ let mut len1 = len1;
+ let mut len2 = len2;
+
+ array[dest] <-> array[c2];
+ dest += 1; c2 += 1; len2 -= 1;
+
+ if len2 == 0 {
+ unsafe {
+ moveVec(array, dest, self.tmp, 0, len1);
+ vec::raw::set_len(self.tmp, 0); // Forget the elements
+ }
+ return;
+ }
+ if len1 == 1 {
+ unsafe {
+ moveVec(array, dest, array, c2, len2);
+ array[dest+len2] <-> self.tmp[c1];
+ vec::raw::set_len(self.tmp, 0); // Forget the element
+ }
+ return;
+ }
+
+ let mut minGallop = self.minGallop;
+ loop {
+ let mut count1 = 0;
+ let mut count2 = 0;
+ let mut breakOuter = false;
+
+ loop {
+ assert len1 > 1 && len2 != 0;
+ if array[c2] < self.tmp[c1] {
+ array[dest] <-> array[c2];
+ dest += 1; c2 += 1; len2 -= 1;
+ count2 += 1; count1 = 0;
+ if len2 == 0 {
+ breakOuter = true;
+ }
+ } else {
+ array[dest] <-> self.tmp[c1];
+ dest += 1; c1 += 1; len1 -= 1;
+ count1 += 1; count2 = 0;
+ if len1 == 1 {
+ breakOuter = true;
+ }
+ }
+ if breakOuter || ((count1 | count2) >= minGallop) {
+ break;
+ }
+ }
+ if breakOuter { break; }
+
+ // Start to gallop
+ loop {
+ assert len1 > 1 && len2 != 0;
+
+ let tmpView = vec::mut_view(self.tmp, c1, c1+len1);
+ count1 = gallopRight(&const array[c2], tmpView, 0);
+ if count1 != 0 {
+ unsafe {
+ moveVec(array, dest, self.tmp, c1, count1);
+ }
+ dest += count1; c1 += count1; len1 -= count1;
+ if len1 <= 1 { breakOuter = true; break; }
+ }
+ array[dest] <-> array[c2];
+ dest += 1; c2 += 1; len2 -= 1;
+ if len2 == 0 { breakOuter = true; break; }
+
+ let tmpView = vec::mut_view(array, c2, c2+len2);
+ count2 = gallopLeft(&const self.tmp[c1], tmpView, 0);
+ if count2 != 0 {
+ unsafe {
+ moveVec(array, dest, array, c2, count2);
+ }
+ dest += count2; c2 += count2; len2 -= count2;
+ if len2 == 0 { breakOuter = true; break; }
+ }
+ array[dest] <-> self.tmp[c1];
+ dest += 1; c1 += 1; len1 -= 1;
+ if len1 == 1 { breakOuter = true; break; }
+ minGallop -= 1;
+ if !(count1 >= MIN_GALLOP || count2 >= MIN_GALLOP) { break; }
+ }
+ if breakOuter { break; }
+ if minGallop < 0 { minGallop = 0; }
+ minGallop += 2; // Penalize for leaving gallop
+ }
+ self.minGallop = if minGallop < 1 { 1 } else { minGallop };
+
+ if len1 == 1 {
+ assert len2 > 0;
+ unsafe {
+ moveVec(array, dest, array, c2, len2);
+ }
+ array[dest+len2] <-> self.tmp[c1];
+ } else if len1 == 0 {
+ fail fmt!("Method mergeLo violates its contract! %?", len1);
+ } else {
+ assert len2 == 0;
+ assert len1 > 1;
+ unsafe {
+ moveVec(array, dest, self.tmp, c1, len1);
+ }
+ }
+ unsafe { vec::raw::set_len(self.tmp, 0); }
+ }
+
+ fn mergeHi(array: &[mut T], base1: uint, len1: uint, base2: uint, len2: uint) {
+ assert len1 != 1 && len2 != 0 && base1 + len1 == base2;
+
+ vec::reserve(self.tmp, len2);
+
+ unsafe {
+ vec::raw::set_len(self.tmp, len2);
+ moveVec(self.tmp, 0, array, base2, len2);
+ }
+
+ let mut c1 = base1 + len1 - 1;
+ let mut c2 = len2 - 1;
+ let mut dest = base2 + len2 - 1;
+ let mut len1 = len1;
+ let mut len2 = len2;
+
+ array[dest] <-> array[c1];
+ dest -= 1; c1 -= 1; len1 -= 1;
+
+ if len1 == 0 {
+ unsafe {
+ moveVec(array, dest-(len2-1), self.tmp, 0, len2);
+ vec::raw::set_len(self.tmp, 0); // Forget the elements
+ }
+ return;
+ }
+ if len2 == 1 {
+ dest -= len1;
+ c1 -= len1;
+ unsafe {
+ moveVec(array, dest+1, array, c1+1, len1);
+ array[dest] <-> self.tmp[c2];
+ vec::raw::set_len(self.tmp, 0); // Forget the element
+ }
+ return;
+ }
+
+ let mut minGallop = self.minGallop;
+ loop {
+ let mut count1 = 0;
+ let mut count2 = 0;
+ let mut breakOuter = false;
+
+ loop {
+ assert len1 != 0 && len2 > 1;
+ if self.tmp[c2] < array[c1] {
+ array[dest] <-> array[c1];
+ dest -= 1; c1 -= 1; len1 -= 1;
+ count1 += 1; count2 = 0;
+ if len1 == 0 {
+ breakOuter = true;
+ }
+ } else {
+ array[dest] <-> self.tmp[c2];
+ dest -= 1; c2 -= 1; len2 -= 1;
+ count2 += 1; count1 = 0;
+ if len2 == 1 {
+ breakOuter = true;
+ }
+ }
+ if breakOuter || ((count1 | count2) >= minGallop) {
+ break;
+ }
+ }
+ if breakOuter { break; }
+
+ // Start to gallop
+ loop {
+ assert len2 > 1 && len1 != 0;
+
+ let tmpView = vec::mut_view(array, base1, base1+len1);
+ count1 = len1-gallopRight(&const self.tmp[c2], tmpView, len1-1);
+
+ if count1 != 0 {
+ dest -= count1; c1 -= count1; len1 -= count1;
+ unsafe {
+ moveVec(array, dest+1, array, c1+1, count1);
+ }
+ if len1 == 0 { breakOuter = true; break; }
+ }
+
+ array[dest] <-> self.tmp[c2];
+ dest -= 1; c2 -= 1; len2 -= 1;
+ if len2 == 1 { breakOuter = true; break; }
+
+ let tmpView = vec::mut_view(self.tmp, 0, len2);
+ let gL = gallopLeft(&const array[c1], tmpView, len2-1);
+ count2 = len2 - gL;
+ if count2 != 0 {
+ dest -= count2; c2 -= count2; len2 -= count2;
+ unsafe {
+ moveVec(array, dest+1, self.tmp, c2+1, count2);
+ }
+ if len2 <= 1 { breakOuter = true; break; }
+ }
+ array[dest] <-> array[c1];
+ dest -= 1; c1 -= 1; len1 -= 1;
+ if len1 == 0 { breakOuter = true; break; }
+ minGallop -= 1;
+ if !(count1 >= MIN_GALLOP || count2 >= MIN_GALLOP) { break; }
+ }
+
+ if breakOuter { break; }
+ if minGallop < 0 { minGallop = 0; }
+ minGallop += 2; // Penalize for leaving gallop
+ }
+ self.minGallop = if minGallop < 1 { 1 } else { minGallop };
+
+ if len2 == 1 {
+ assert len1 > 0;
+ dest -= len1;
+ c1 -= len1;
+ unsafe {
+ moveVec(array, dest+1, array, c1+1, len1);
+ }
+ array[dest] <-> self.tmp[c2];
+ } else if len2 == 0 {
+ fail fmt!("Method mergeHi violates its contract! %?", len2);
+ } else {
+ assert len1 == 0;
+ assert len2 != 0;
+ unsafe {
+ moveVec(array, dest-(len2-1), self.tmp, 0, len2);
+ }
+ }
+ unsafe { vec::raw::set_len(self.tmp, 0); }
+ }
+
+ fn mergeCollapse(array: &[mut T]) {
+ while self.runs.len() > 1 {
+ let mut n = self.runs.len()-2;
+ let chk = do self.runs.borrow |arr| {
+ if n > 0 && arr[n-1].len <= arr[n].len + arr[n+1].len {
+ if arr[n-1].len < arr[n+1].len { n -= 1; }
+ true
+ } else if arr[n].len <= arr[n+1].len {
+ true
+ } else {
+ false
+ }
+ };
+ if !chk { break; }
+ self.mergeAt(n, array);
+ }
+ }
+
+ fn mergeForceCollapse(array: &[mut T]) {
+ while self.runs.len() > 1 {
+ let mut n = self.runs.len()-2;
+ if n > 0 {
+ do self.runs.borrow |arr| {
+ if arr[n-1].len < arr[n+1].len {
+ n -= 1;
+ }
+ }
+ }
+ self.mergeAt(n, array);
+ }
+ }
+}
+
+// Moves elements to from dest to from
+// Unsafe as it makes the from parameter invalid between s2 and s2+len
+#[inline(always)]
+unsafe fn moveVec<T>(dest: &[mut T], s1: uint, from: &[const T], s2: uint, len: uint) {
+ assert s1+len <= dest.len() && s2+len <= from.len();
+
+ do vec::as_mut_buf(dest) |p, _len| {
+ let destPtr = ptr::mut_offset(p, s1);
+
+ do vec::as_const_buf(from) |p, _len| {
+ let fromPtr = ptr::const_offset(p, s2);
+
+ ptr::memmove(destPtr, fromPtr, len);
+ }
+ }
+}
+
#[cfg(test)]
mod test_qsort3 {
#[legacy_exports];
projects / rust.git / commitdiff