67 lines
1.7 KiB
Python
67 lines
1.7 KiB
Python
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import random
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import time
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def merge_sort(nums):
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length_of_nums = len(nums)
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if length_of_nums < 2:
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return nums
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split = int(length_of_nums / 2)
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split_one = nums[0:split]
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split_two = nums[split:]
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sorted_left_side = merge_sort(split_one)
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sorted_right_side = merge_sort(split_two)
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return merge(sorted_left_side, sorted_right_side)
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def merge(first, second):
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final = []
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i = 0
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j = 0
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while i < len(first) and j < len(second):
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if first[i] <= second[j]:
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final.append(first[i])
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i += 1
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else:
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final.append(second[j])
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j += 1
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if len(first) > 0:
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for item in first[i:]:
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final.append(item)
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if len(second) > 0:
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for item in second[j:]:
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final.append(item)
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return final
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# Create a list of random numbers
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# The size 80,000 is quite large for Bubble Sort
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list_size = 1 * 2 * 3 * 4 * 5 * 6 * 7 * 8 * 9
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num_list = [random.randint(1, 99999) for _ in range(list_size)]
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print(f"Sorting a list of {list_size} numbers using Merge Sort...")
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# --- Start the timer (using perf_counter for better benchmarking) ---
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start_time = time.perf_counter()
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# --- Call the sorting function ---
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sorted_list = merge_sort(num_list) # Store the result without printing immediately
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# sorted_list = sorted(num_list)
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# --- Stop the timer ---
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end_time = time.perf_counter()
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# --- Calculate and print elapsed time ---
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elapsed_time = end_time - start_time
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print(f"Elapsed time: {elapsed_time:.4f} seconds")
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# --- Optional: Print a small portion of the sorted list to verify ---
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print("First 10 elements of sorted list:", sorted_list[:10])
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print("Last 10 elements of sorted list:", sorted_list[-10:])
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