53 lines
1.1 KiB
Go
53 lines
1.1 KiB
Go
package tools
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import (
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"math/rand"
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"time"
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)
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var (
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Rand *randMod
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)
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type randMod struct {
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}
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// RandomAll 按权重随机选取 N 个不重复的元素
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func (m *randMod) RandomAll(data map[int]int, n int) []int {
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if n > len(data) {
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return nil
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}
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rand.Seed(time.Now().UnixNano())
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// 复制权重映射，避免修改原始数据
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remainingWeights := make(map[int]int)
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for k, v := range data {
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remainingWeights[k] = v
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}
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result := make([]int, 0, n)
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for i := 0; i < n; i++ {
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totalWeight := 0
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// 计算剩余元素的总权重
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for _, weight := range remainingWeights {
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totalWeight += weight
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}
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if totalWeight == 0 {
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break
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}
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// 生成一个 0 到总权重之间的随机数
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randomNum := rand.Intn(totalWeight)
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currentWeight := 0
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for key, weight := range remainingWeights {
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currentWeight += weight
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if randomNum < currentWeight {
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// 将选中的元素添加到结果切片中
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result = append(result, key)
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// 从剩余权重映射中移除选中的元素
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delete(remainingWeights, key)
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break
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}
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}
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}
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return result
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}
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