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按go中的v[i]/w[i]对i的数组进行排序

go sorting

lyfeng · 技术社区 · 8 年前

我希望按以下顺序对索引数组进行排序 v[i]/w[i] 哪里 v 和 w 是另外两个整数数组。以下是我在Go中的尝试:

package main
import "fmt"
import "sort"

func main() {
    v := [3]int{5, 6, 3}
    w := [3]int{4, 5, 2}
    indices := make([]int, 3)
    for i := range indices {
        indices[i] = i
    }
    sort.Slice(indices, func(a, b int) bool {
        return float32(v[a])/float32(w[a]) > float32(v[b])/float32(w[b])
    })
    fmt.Println(indices)
}

我预计产量 [2,0,1] 因为 3/2>5/4>6/5 但实际产量是 [0,2,1] . 有人能帮我找出问题所在吗?谢谢您。

3 回复 | 直到 8 年前

Uvelichitel 8 年前

sort.Slice(indices, func(a, b int) bool {
        return float32(v[indices[a]])/float32(w[indices[a]]) > float32(v[indices[b]])/float32(w[indices[b]])
    })

Playground

JimB 8 年前

w v indices

sort.Slice(indices, func(i, j int) bool {
    return float64(v[indices[i]])/float64(w[indices[i]]) > float64(v[indices[j]])/float64(w[indices[j]])
})

https://play.golang.org/p/6oFBM27bVR-

type indexSorter struct {
    indices, w, v []int
}

func (a indexSorter) Len() int { return len(a.indices) }
func (a indexSorter) Swap(i, j int) {
    a.indices[i], a.indices[j] = a.indices[j], a.indices[i]
    a.w[i], a.w[j] = a.w[j], a.w[i]
    a.v[i], a.v[j] = a.v[j], a.v[i]
}
func (a indexSorter) Less(i, j int) bool {
    return float64(a.v[i])/float64(a.w[i]) > float64(a.v[i])/float64(a.w[j])
}

https://play.golang.org/p/EFUkHWgjo5U