更新了公开课相关资源

公开课/文档/第05次公开课/code/example01.py

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+nums = []
+for i in range(100000):
+    nums.append(i)
+nums.reverse()
+print(nums)

公开课/文档/第05次公开课/code/example02.py

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+nums = []
+for i in range(100000):
+    nums.insert(0, i)
+print(nums)

公开课/文档/第05次公开课/code/example03.py

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+a, b = 0, 1
+for num in range(1, 101):
+    a, b = b, a + b
+    print(f'{num}: {a}')
+

公开课/文档/第05次公开课/code/example04.py

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+from functools import lru_cache
+
+
+@lru_cache()
+def fib(num):
+    if num in (1, 2):
+        return 1
+    return fib(num - 1) + fib(num - 2)
+
+
+for num in range(1, 101):
+    print(f'{num}: {fib(num)}')

公开课/文档/第05次公开课/code/example05.py

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+"""
+公鸡5元一只，母鸡3元一只，小鸡1元三只，用100元买一百只鸡，问公鸡、母鸡、小鸡各有多少只？
+"""
+for x in range(21):
+    for y in range(34):
+        z = 100 - x - y
+        if z % 3 == 0 and 5 * x + 3 * y + z // 3 == 100:
+            print(x, y, z)
+

公开课/文档/第05次公开课/code/example06.py

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+import re
+
+import PyPDF2
+
+with open('Python_Tricks_encrypted.pdf', 'rb') as pdf_file_stream:
+    reader = PyPDF2.PdfFileReader(pdf_file_stream)
+    with open('dictionary.txt', 'r') as txt_file_stream:
+        file_iter = iter(lambda: txt_file_stream.readline(), '')
+        for word in file_iter:
+            word = re.sub(r'\s', '', word)
+            if reader.decrypt(word):
+                print(word)
+                break
+

公开课/文档/第06次公开课/code/example01.py

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+import sys
+
+
+def fac(num):
+    if num == 0:
+        return 1
+    return num * fac(num - 1)
+
+
+def main():
+    print(fac(59996))
+
+
+if __name__ == '__main__':
+    sys.setrecursionlimit(60000)
+    main()
+# for i in range(1000):
+#     print(f'{i}:'.rjust(3), fac(i))
+

公开课/文档/第06次公开课/code/example02.py

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+def climb(num):
+    a, b, c = 1, 2, 4
+    for _ in range(num - 1):
+        a, b, c = b, c, a + b + c
+    return a
+
+
+def main():
+    n = int(input('台阶数量: '))
+    print(climb(n))
+
+
+if __name__ == '__main__':
+    main()

公开课/文档/第06次公开课/code/example03.py

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+"""
+迷宫寻路
+"""
+import random
+import sys
+
+WALL = -1
+ROAD = 0
+
+ROWS = 10
+COLS = 10
+
+
+def find_way(maze, i=0, j=0, step=1):
+    """走迷宫"""
+    if 0 <= i < ROWS and 0 <= j < COLS and maze[i][j] == 0:
+        maze[i][j] = step
+        if i == ROWS - 1 and j == COLS - 1:
+            print('=' * 20)
+            display(maze)
+            sys.exit(0)
+        find_way(maze, i + 1, j, step + 1)
+        find_way(maze, i, j + 1, step + 1)
+        find_way(maze, i - 1, j, step + 1)
+        find_way(maze, i, j - 1, step + 1)
+        maze[i][j] = ROAD
+
+
+def reset(maze):
+    """重置迷宫"""
+    for i in range(ROWS):
+        for j in range(COLS):
+            num = random.randint(1, 10)
+            maze[i][j] = WALL if num > 7 else ROAD
+    maze[0][0] = maze[ROWS - 1][COLS - 1] = ROAD
+
+
+def display(maze):
+    """显示迷宫"""
+    for row in maze:
+        for col in row:
+            if col == -1:
+                print('■', end=' ')
+            elif col == 0:
+                print('□', end=' ')
+            else:
+                print(f'{col}'.ljust(2), end='')
+        print()
+
+
+def main():
+    """主函数"""
+    maze = [[0] * COLS for _ in range(ROWS)]
+    reset(maze)
+    display(maze)
+    find_way(maze)
+    print('没有出路!!!')
+
+
+if __name__ == '__main__':
+    main()

公开课/文档/第06次公开课/code/example04.py

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+"""
+骑士巡逻
+"""
+import sys
+
+SIZE = 8
+
+
+def display(board):
+    """显示棋盘"""
+    for row in board:
+        for col in row:
+            print(f'{col}'.rjust(2, '0'), end=' ')
+        print()
+
+
+def patrol(board, i=0, j=0, step=1):
+    """巡逻"""
+    if 0 <= i < SIZE and 0 <= j < SIZE and board[i][j] == 0:
+        board[i][j] = step
+        if step == SIZE * SIZE:
+            display(board)
+            sys.exit(0)
+        patrol(board, i + 1, j + 2, step + 1)
+        patrol(board, i + 2, j + 1, step + 1)
+        patrol(board, i + 2, j - 1, step + 1)
+        patrol(board, i + 1, j - 2, step + 1)
+        patrol(board, i - 1, j - 2, step + 1)
+        patrol(board, i - 2, j - 1, step + 1)
+        patrol(board, i - 2, j + 1, step + 1)
+        patrol(board, i - 1, j + 2, step + 1)
+        board[i][j] = 0
+
+
+def main():
+    """主函数"""
+    board = [[0] * SIZE for _ in range(SIZE)]
+    patrol(board)
+
+
+if __name__ == '__main__':
+    main()

公开课/文档/第06次公开课/code/example05.py

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+size = 25
+
+for i in range(size):
+    for j in range(size):
+        if i % 2 == 1 or j % 2 == 1:
+            print('■', end='')
+        else:
+            print('□', end='')
+    print()
+