go语言map根据值排序

func SortMapByValue(m map[string]int)  []impounds {
	var l []impounds
	for k,v := range m{
		l=append(l, impounds{k,v})
	}
	sort.Slice(l, func(i, j int) bool {
		return l[i].Val > l[j].Val  // 降序
	})
	return l

}