39 lines
711 B
Go
Vendored
39 lines
711 B
Go
Vendored
// Copyright 2013 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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//go:build !go1.2
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// +build !go1.2
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package language
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import "sort"
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func sortStable(s sort.Interface) {
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ss := stableSort{
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s: s,
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pos: make([]int, s.Len()),
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}
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for i := range ss.pos {
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ss.pos[i] = i
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}
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sort.Sort(&ss)
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}
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type stableSort struct {
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s sort.Interface
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pos []int
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}
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func (s *stableSort) Len() int {
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return len(s.pos)
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}
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func (s *stableSort) Less(i, j int) bool {
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return s.s.Less(i, j) || !s.s.Less(j, i) && s.pos[i] < s.pos[j]
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}
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func (s *stableSort) Swap(i, j int) {
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s.s.Swap(i, j)
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s.pos[i], s.pos[j] = s.pos[j], s.pos[i]
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}
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