Golang sort.SliceStable 在排序后返回不一样的结果

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我使用sort.slicestable作为map[string]int，它从txt文件中读取，但排序后结果不同。我尝试过将映射转换为结构或切片，但是 ethier 磨损了，这通常是结果吗？ 代码：

func teststableuseslice() {
    counts := make(map[string]int)
    f, err := os.open("/users/boroughfan/gitdocuments/golangpractise/ch01/dup/text_feel_the_light_lyrics.txt")
    if err != nil {
        fmt.fprintf(os.stderr, "dup:%v\n", err)
    }
    input := bufio.newscanner(f)
    for input.scan() {
        counts[input.text()]++
    }
    f.close()
    ///////////////////////////////////////////////////////////
    linesslice := make([]string, 0, len(counts))

    for line := range counts {
        linesslice = append(linesslice, line)
    }
    sort.slicestable(linesslice, func(i, j int) bool {
        return counts[linesslice[i]] < counts[linesslice[j]]
    })

    for _, line := range linesslice {
        fmt.printf("%d\t%s\n", counts[line], line)
    }
}
func teststableusepair() {
    counts := make(map[string]int)
    f, err := os.open("/users/boroughfan/gitdocuments/golangpractise/ch01/dup/text_feel_the_light_lyrics.txt")
    if err != nil {
        fmt.fprintf(os.stderr, "dup:%v\n", err)
    }
    input := bufio.newscanner(f)
    for input.scan() {
        counts[input.text()]++
    }
    f.close()
    ///////////////////////////////////////////////////////////
    pairlist := make([]pair, 0, len(counts))
    for line := range counts {
        pairlist = append(pairlist, pair{line, counts[line]})
    }
    sort.slicestable(pairlist, func(i, j int) bool { return pairlist[i].value < pairlist[j].value })
    for _, pairs := range pairlist {
        fmt.printf("%d\t%s\n", pairs.value, pairs.key)
    }
}

这是txt文件：

// this is the dup test file, contents are from the feel the light lyrics
"Feel The Light"
(from "Home" soundtrack)
Hmm, hmm
Hmm
Here I go, here I go
Feel better now, feel better now
Here I go, here I go
It's better now, feel better now
Do you remember when we fell under
Did you expect me to reason with thunder
I still remember when time was frozen
What seemed forever was just a moment
Hurry up, hurry up
There's no more waiting
We're still worth saving
Feel the light
Shining in the dark of night
Remember what we forgot
I know it's a long shot
But we're bringing it all back
We're bringing it all back
Feel the light
Shining like the stars tonight
Remember what we forgot
I know it's a long shot
But we're bringing it all back
We're bringing it all back
Here I go, here I go
Feel better now, feel better now
Here I go, here I go
It's better now, feel better now
I still remember when things were broken
But put together the cracks we'll close in
Hurry up, hurry up
There's no more waiting
We're still worth saving
Feel the light
Shining in the dark of night
Remember what we forgot
I know it's a long shot
But we're bringing it all back
We're bringing it all back
Feel the light
Shining like the stars tonight
Remember what we forgot
I know it's a long shot
But we're bringing it all back
We're bringing it all back
You and I can have it all tonight
So let's bring it back to life
Now we have another chance to fly
Another chance to make it right
Feel the light
Shining in the dark of night
Remember what we forgot
I know it's a long shot
Feel the light
Shining like the stars tonight
Remember what we forgot
I know it's a long shot
But we're bringing it all back
We're bringing it all back
Here we go, here we go
Feel better now, feel better now
Here we go, here we go
It's better now, feel better now

正确答案

for line := range counts {
   ...

将按照地图给出的随机顺序枚举存储在 counts 地图中的线。

sort.slicestable() 的“稳定”部分不会取消文本中出现次数相同的两行的随机化 - 恰恰相反：它将保留此类行的初始顺序。

例如：

“我们开始，我们开始” 和 “我们仍然值得保存” 都有计数 2，所以：

如果 “我们开始，我们开始” 出现在 “我们仍然值得保存” 之前（或之后）在您的初始切片中，它将保留在结果切片之前（或之后）调用 sort.slicestable() 后。

如果您想要一致的顺序，请选择一种对它们之间的行进行完全排序的方法：

sort.SliceStable(linesSlice, func(i, j int) bool {
        if counts[linesSlice[i]] != counts[linesSlice[j]] {
            return counts[linesSlice[i]] < counts[linesSlice[j]]
        }
        // in this example: if lines have same count, order them alphabetically:
        return linesSlice[i] < linesSlice[j]
    })

（请注意，如果元素之间的顺序完整，则不再需要 stable）

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