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91 lines
1.9 KiB
91 lines
1.9 KiB
"""
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File: space_complexity.py
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Created Time: 2022-11-25
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Author: krahets (krahets@163.com)
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"""
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import sys
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from pathlib import Path
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sys.path.append(str(Path(__file__).parent.parent))
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from modules import ListNode, TreeNode, print_tree
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def function() -> int:
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"""Function"""
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# Perform some operations
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return 0
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def constant(n: int):
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"""Constant complexity"""
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# Constants, variables, objects occupy O(1) space
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a = 0
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nums = [0] * 10000
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node = ListNode(0)
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# Variables in a loop occupy O(1) space
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for _ in range(n):
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c = 0
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# Functions in a loop occupy O(1) space
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for _ in range(n):
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function()
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def linear(n: int):
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"""Linear complexity"""
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# A list of length n occupies O(n) space
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nums = [0] * n
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# A hash table of length n occupies O(n) space
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hmap = dict[int, str]()
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for i in range(n):
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hmap[i] = str(i)
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def linear_recur(n: int):
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"""Linear complexity (recursive implementation)"""
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print("Recursive n =", n)
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if n == 1:
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return
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linear_recur(n - 1)
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def quadratic(n: int):
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"""Quadratic complexity"""
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# A two-dimensional list occupies O(n^2) space
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num_matrix = [[0] * n for _ in range(n)]
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def quadratic_recur(n: int) -> int:
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"""Quadratic complexity (recursive implementation)"""
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if n <= 0:
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return 0
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# Array nums length = n, n-1, ..., 2, 1
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nums = [0] * n
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return quadratic_recur(n - 1)
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def build_tree(n: int) -> TreeNode | None:
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"""Exponential complexity (building a full binary tree)"""
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if n == 0:
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return None
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root = TreeNode(0)
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root.left = build_tree(n - 1)
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root.right = build_tree(n - 1)
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return root
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"""Driver Code"""
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if __name__ == "__main__":
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n = 5
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# Constant complexity
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constant(n)
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# Linear complexity
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linear(n)
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linear_recur(n)
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# Quadratic complexity
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quadratic(n)
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quadratic_recur(n)
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# Exponential complexity
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root = build_tree(n)
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print_tree(root)
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