Source file doc/progs/sort.go

// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package sort

type Interface interface {
    Len() int
    Less(i, j int) bool
    Swap(i, j int)
}

func Sort(data Interface) {
    for i := 1; i < data.Len(); i++ {
        for j := i; j > 0 && data.Less(j, j-1); j-- {
            data.Swap(j, j-1)
        }
    }
}

func IsSorted(data Interface) bool {
    n := data.Len()
    for i := n - 1; i > 0; i-- {
        if data.Less(i, i-1) {
            return false
        }
    }
    return true
}

// Convenience types for common cases

type IntArray []int

func (p IntArray) Len() int           { return len(p) }
func (p IntArray) Less(i, j int) bool { return p[i] < p[j] }
func (p IntArray) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }


type FloatArray []float

func (p FloatArray) Len() int           { return len(p) }
func (p FloatArray) Less(i, j int) bool { return p[i] < p[j] }
func (p FloatArray) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }


type StringArray []string

func (p StringArray) Len() int           { return len(p) }
func (p StringArray) Less(i, j int) bool { return p[i] < p[j] }
func (p StringArray) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }


// Convenience wrappers for common cases

func SortInts(a []int)       { Sort(IntArray(a)) }
func SortFloats(a []float)   { Sort(FloatArray(a)) }
func SortStrings(a []string) { Sort(StringArray(a)) }


func IntsAreSorted(a []int) bool       { return IsSorted(IntArray(a)) }
func FloatsAreSorted(a []float) bool   { return IsSorted(FloatArray(a)) }
func StringsAreSorted(a []string) bool { return IsSorted(StringArray(a)) }