def merge(arr, left, mid, right): n1 = mid - left + 1 n2 = right- mid # 创建临时数组 L = arr[left:mid+1] R = arr[mid+1:right+1] # 归并临时数组到 arr[l..r] i = 0 # 初始化第一个子数组的索引 j = 0 # 初始化第二个子数组的索引 k = left # 初始归并子数组的索引 while i < n1 and j < n2 : if L[i] <= R[j]: arr[k] = L[i] i += 1 else: arr[k] = R[j] j += 1 k += 1 # 拷贝 L[] 的保留元素 while i < n1: arr[k] = L[i] i += 1 k += 1 # 拷贝 R[] 的保留元素 while j < n2: arr[k] = R[j] j += 1 k += 1 def mergeSort(arr,left,right): if left < right: mid = (left+right)//2 mergeSort(arr, left, mid) mergeSort(arr, mid+1, right) merge(arr, left, mid, right) if __name__ =="__main__": 补充代码
时间: 2024-02-14 12:14:54 浏览: 243
如果您需要补充代码,可以参考以下完整的Python代码实现:
```python
def merge(arr, left, mid, right):
n1 = mid - left + 1
n2 = right- mid
# 创建临时数组
L = arr[left:mid+1]
R = arr[mid+1:right+1]
# 归并临时数组到 arr[l..r]
i = 0 # 初始化第一个子数组的索引
j = 0 # 初始化第二个子数组的索引
k = left # 初始归并子数组的索引
while i < n1 and j < n2 :
if L[i] <= R[j]:
arr[k] = L[i]
i += 1
else:
arr[k] = R[j]
j += 1
k += 1
# 拷贝 L[] 的保留元素
while i < n1:
arr[k] = L[i]
i += 1
k += 1
# 拷贝 R[] 的保留元素
while j < n2:
arr[k] = R[j]
j += 1
k += 1
def mergeSort(arr,left,right):
if left < right:
mid = (left+right)//2
mergeSort(arr, left, mid)
mergeSort(arr, mid+1, right)
merge(arr, left, mid, right)
if __name__ =="__main__":
arr = [38,27,43,3,9,82,10]
n = len(arr)
mergeSort(arr,0,n-1)
print ("排序后的数组:")
for i in range(n):
print ("%d" %arr[i],end=" ")
```
这段代码实现了归并排序算法,其中merge函数用来合并两个有序数组,mergeSort函数用来递归调用归并排序,最后在主函数中对一个未排序的数组进行排序并输出结果。
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