merge sort in golang

package mainimport ("fmt")var tmp [len(src)]intvar src = [7]int{2, 4, 9, 7, 6, 1, 9}//对排序好的分数组进行合并func Merge(left, m, right int) {i := leftj := left //标示把排序好的数放到临时数组的那个indexw := m + 1//比较，把比较小的数字放到临时数组中去for i <= m && w <= right {if src[i] >= src[w] {tmp[j] = src[w]w += 1} else {tmp[j] = src[i]i += 1}j += 1}//把剩余数组中的数字依次copy到临时数组中去for i <= m {tmp[j] = src[i]i += 1j += 1}for w <= right {tmp[j] = src[w]w += 1j += 1}//把临时数组的数据copy到原数组中for left <= right {src[left] = tmp[left]left += 1}}func MergeSort(left, right int) {if left >= right {return}m := (left + right) / 2MergeSort(left, m)MergeSort(m+1, right)Merge(left, m, right)}func main() {MergeSort(0, len(src)-1)fmt.Println(src)}

归并排序是经典的divide conquer算法。基本思想很简单，但是写代码的时候，要小心各种边界值和index的变换。