权重实现随机抽奖

一般抽奖是怎么实现的？在实习期间学会了一种通用的写法，在这里记录一下。

最近在学Golang语法基础，这里就用Golang来写。

package main

import (
    "fmt"
    "time"
    "math/rand"
)

func main() {
    r := rand.New(rand.NewSource(time.Now().UnixNano()))

    weights  := [9]int{1,2,3,50,7,51,68,54,89}
    var total_weight int
    for i := 0; i < 9; i++ {
        total_weight += weights[i]
    }
    
    println("total_weight = ", total_weight)
    cur_weight := r.Intn(total_weight)
    fmt.Println("cur_weight =",cur_weight)
    for i:=0; i<9; i++ {
        if cur_weight < weights[i] {
            fmt.Println("weight_num =",i)
            break
        }

        cur_weight -= weights[i]
    }
}