You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
hello-algo/zh-hant/codes/python/chapter_computational_compl.../space_complexity.py

91 lines
1.8 KiB

"""
File: space_complexity.py
Created Time: 2022-11-25
Author: krahets (krahets@163.com)
"""
import sys
from pathlib import Path
sys.path.append(str(Path(__file__).parent.parent))
from modules import ListNode, TreeNode, print_tree
def function() -> int:
"""函式"""
# 執行某些操作
return 0
def constant(n: int):
"""常數階"""
# 常數、變數、物件佔用 O(1) 空間
a = 0
nums = [0] * 10000
node = ListNode(0)
# 迴圈中的變數佔用 O(1) 空間
for _ in range(n):
c = 0
# 迴圈中的函式佔用 O(1) 空間
for _ in range(n):
function()
def linear(n: int):
"""線性階"""
# 長度為 n 的串列佔用 O(n) 空間
nums = [0] * n
# 長度為 n 的雜湊表佔用 O(n) 空間
hmap = dict[int, str]()
for i in range(n):
hmap[i] = str(i)
def linear_recur(n: int):
"""線性階(遞迴實現)"""
print("遞迴 n =", n)
if n == 1:
return
linear_recur(n - 1)
def quadratic(n: int):
"""平方階"""
# 二維串列佔用 O(n^2) 空間
num_matrix = [[0] * n for _ in range(n)]
def quadratic_recur(n: int) -> int:
"""平方階(遞迴實現)"""
if n <= 0:
return 0
# 陣列 nums 長度為 n, n-1, ..., 2, 1
nums = [0] * n
return quadratic_recur(n - 1)
def build_tree(n: int) -> TreeNode | None:
"""指數階(建立滿二元樹)"""
if n == 0:
return None
root = TreeNode(0)
root.left = build_tree(n - 1)
root.right = build_tree(n - 1)
return root
"""Driver Code"""
if __name__ == "__main__":
n = 5
# 常數階
constant(n)
# 線性階
linear(n)
linear_recur(n)
# 平方階
quadratic(n)
quadratic_recur(n)
# 指數階
root = build_tree(n)
print_tree(root)