045 常见排序算法
更新、更全的《Go从入门到放弃》的更新网站，更有python、go、人工智能教学等着你：https://www.cnblogs.com/nickchen121/p/11517502.html
本文介绍了Go语言版经典的排序算法–快速排序、归并排序和堆排序。
一、排序算法
1.1 快速排序
func quickSort(data []int) {
if len(data) <= 1 {
return
}
base := data[0]
l, r := 0, len(data)-1
for i := 1; i <= r; {
if data[i] > base {
data[i], data[r] = data[r], data[i]
r--
} else {
data[i], data[l] = data[l], data[i]
l++
i++
}
}
quickSort(data[:l])
quickSort(data[l+1:])
}
func main() {
s := make([]int, 0, 16)
for i := 0; i < 16; i++ {
s = append(s, rand.Intn(100))
}
fmt.Println(s)
quickSort(s)
fmt.Println(s)
}
1.2 归并排序
func mergeSort(data []int) []int {
length := len(data)
if length <= 1 {
return data
}
num := length / 2
left := mergeSort(data[:num])
right := mergeSort(data[num:])
return merge(left, right)
}
func merge(left, right []int) (result []int) {
l, r := 0, 0
for l < len(left) && r < len(right) {
if left[l] < right[r] {
result = append(result, left[l])
l++
} else {
result = append(result, right[r])
r++
}
}
result = append(result, left[l:]...)
result = append(result, right[r:]...)
return
}
func main() {
s := make([]int, 0, 16)
for i := 0; i < 16; i++ {
s = append(s, rand.Intn(100))
}
fmt.Println(s)
s = mergeSort(s)
fmt.Println(s)
}
1.3 堆排序
func heapSort(array []int) {
m := len(array)
s := m / 2
for i := s; i > -1; i-- {
heap(array, i, m-1)
}
for i := m - 1; i > 0; i-- {
array[i], array[0] = array[0], array[i]
heap(array, 0, i-1)
}
}
func heap(array []int, i, end int) {
l := 2*i + 1
if l > end {
return
}
n := l
r := 2*i + 2
if r <= end && array[r] > array[l] {
n = r
}
if array[i] > array[n] {
return
}
array[n], array[i] = array[i], array[n]
heap(array, n, end)
}
func main() {
s := make([]int, 0, 16)
for i := 0; i < 16; i++ {
s = append(s, rand.Intn(100))
}
fmt.Println(s)
heapSort(s)
fmt.Println(s)
}
