排序算法比较代码，要求：用随机数产生100000个待排序元素的关键字值，测试排序函数的机器实际执行时间

以下是使用 Python 实现常见排序算法的比较代码，使用随机数生成100000个待排序元素并输出每个算法的执行时间：

import random
import time

# 生成随机数组
arr = [random.randint(1, 1000) for _ in range(100000)]

# 冒泡排序
def bubble_sort(arr):
    n = len(arr)
    for i in range(n):
        for j in range(n-i-1):
            if arr[j] > arr[j+1]:
                arr[j], arr[j+1] = arr[j+1], arr[j]

start_time = time.time()
bubble_sort(arr)
end_time = time.time()
print("Bubble Sort:", end_time - start_time)

# 选择排序
def selection_sort(arr):
    n = len(arr)
    for i in range(n):
        min_idx = i
        for j in range(i+1, n):
            if arr[j] < arr[min_idx]:
                min_idx = j
        arr[i], arr[min_idx] = arr[min_idx], arr[i]

start_time = time.time()
selection_sort(arr)
end_time = time.time()
print("Selection Sort:", end_time - start_time)

# 插入排序
def insertion_sort(arr):
    n = len(arr)
    for i in range(1, n):
        key = arr[i]
        j = i-1
        while j >= 0 and key < arr[j]:
            arr[j+1] = arr[j]
            j -= 1
        arr[j+1] = key

start_time = time.time()
insertion_sort(arr)
end_time = time.time()
print("Insertion Sort:", end_time - start_time)

# 快速排序
def quick_sort(arr, low, high):
    if low < high:
        pi = partition(arr, low, high)
        quick_sort(arr, low, pi-1)
        quick_sort(arr, pi+1, high)

def partition(arr, low, high):
    pivot = arr[high]
    i = low-1
    for j in range(low, high):
        if arr[j] < pivot:
            i += 1
            arr[i], arr[j] = arr[j], arr[i]
    arr[i+1], arr[high] = arr[high], arr[i+1]
    return i+1

start_time = time.time()
quick_sort(arr, 0, len(arr)-1)
end_time = time.time()
print("Quick Sort:", end_time - start_time)

# 归并排序
def merge_sort(arr):
    if len(arr) > 1:
        mid = len(arr) // 2
        left_half = arr[:mid]
        right_half = arr[mid:]

        merge_sort(left_half)
        merge_sort(right_half)

        i = j = k = 0
        while i < len(left_half) and j < len(right_half):
            if left_half[i] < right_half[j]:
                arr[k] = left_half[i]
                i += 1
            else:
                arr[k] = right_half[j]
                j += 1
            k += 1

        while i < len(left_half):
            arr[k] = left_half[i]
            i += 1
            k += 1

        while j < len(right_half):
            arr[k] = right_half[j]
            j += 1
            k += 1

start_time = time.time()
merge_sort(arr)
end_time = time.time()
print("Merge Sort:", end_time - start_time)

注意，不同机器的运行时间可能会有所不同。