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go实现快速排序

package main
 
import (
    "log"
)
 
var c = 0
 
func main() {
 
    var aa []int = []int{5, 2, 3, 11, 13, 27, 1, 38, 0, 6, 4, 7, 9, 15, 33, 30}
    log.Println(aa)
    qs(aa)
    log.Println(aa)
    // log.Println("quick sort result: ", quickSort(aa))
 
}
/*
func quickSort(s []int) []int {
    if len(s) < 2 {
        return s
    }
 
    v := s[0]
    var left, right []int
    for _, e := range s[1:] {
        if e <= v {
            left = append(left, e)
        } else {
            right = append(right, e)
        }
    }
 
    // 实现了“quickSort(left) + v + quickSort(right)”的操作
    return append(append(quickSort(left), v), quickSort(right)...)
}
*/
 
func qs(a []int) {
    c++
    log.Println("agin", a)
    flag := a[0]
    l := 0
    r := len(a) - 1
    bb := false
    for l <= r {
 
        if bb == true {
            if a[l] > flag {
                a[r] = a[l]
                bb = false
                r--
            } else {
                l++
            }
 
        } else {
            if a[r] < flag {
                a[l] = a[r]
                bb = true
                l++
            } else {
                r--
            }
 
        }
        if l == r {
 
            a[l] = flag
            log.Println("swap", a)
            // 先序遍历
            if l >= 2 {
                log.Println("in1", c, l, a)
                qs(a[0:l])
            }
            if len(a)-l >= 3 {
                log.Println("in2", c, l, a)
                qs(a[l+1 : len(a)])
            }
        }
 
    }
 
}