pythone中len

len() 函数是 Python 内置函数之一，用于返回一个容器（如字符串、列表、元组等）的长度或者元素个数。使用 len() 函数可以获取容器的大小，具体取决于容器中的元素数量。例如：

string = "Hello, World!"
length = len(string)
print(length)  # 输出：13

my_list = [1, 2, 3, 4, 5]
length = len(my_list)
print(length)  # 输出：5

在上述例子中，`len()` 函数分别返回了字符串 "Hello, World!" 和列表 [1, 2, 3, 4, 5] 的长度。

相关问题

pythone贪吃蛇代码

下面是一个简单的 Python 贪吃蛇游戏代码示例：

import pygame
import time

pygame.init()

white = (255, 255, 255)
yellow = (255, 255, 102)
black = (0, 0, 0)
red = (213, 50, 80)
green = (0, 255, 0)
blue = (50, 153, 213)

dis_width = 800
dis_height = 600

dis = pygame.display.set_mode((dis_width, dis_height))
pygame.display.set_caption('贪吃蛇游戏')

clock = pygame.time.Clock()

snake_block = 10
snake_speed = 30

font_style = pygame.font.SysFont(None, 50)
score_font = pygame.font.SysFont(None, 35)


def our_snake(snake_block, snake_list):
    for x in snake_list:
        pygame.draw.rect(dis, green, [x[0], x[1], snake_block, snake_block])


def message(msg, color):
    mesg = font_style.render(msg, True, color)
    dis.blit(mesg, [dis_width / 6, dis_height / 3])


def gameLoop():
    game_over = False
    game_close = False

    x1 = dis_width / 2
    y1 = dis_height / 2
    x1_change = 0
    y1_change = 0

    snake_List = []
    Length_of_snake = 1

    foodx = round(
        round(dis_width - snake_block) / 3.13 / snake_block) * snake_block
    foody = round(
        round(dis_height - snake_block) / 2.08 / snake_block) * snake_block

    while not game_over:

        while game_close == True:
            dis.fill(blue)
            message("你输了！按Q-退出或C-重新开始", red)
            pygame.display.update()

            for event in pygame.event.get():
                if event.type == pygame.KEYDOWN:
                    if event.key == pygame.K_q:
                        game_over = True
                        game_close = False
                    if event.key == pygame.K_c:
                        gameLoop()

        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                game_over = True
            if event.type == pygame.KEYDOWN:
                if event.key == pygame.K_LEFT:
                    x1_change = -snake_block
                    y1_change = 0
                elif event.key == pygame.K_RIGHT:
                    x1_change = snake_block
                    y1_change = 0
                elif event.key == pygame.K_UP:
                    y1_change = -snake_block
                    x1_change = 0
                elif event.key == pygame.K_DOWN:
                    y1_change = snake_block
                    x1_change = 0

        if x1 >= dis_width or x1 < 0 or y1 >= dis_height or y1 < 0:
            game_close = True

        x1 += x1_change
        y1 += y1_change
        dis.fill(blue)
        pygame.draw.rect(dis, yellow, [
                         foodx, foody, snake_block, snake_block])
        snake_Head = []
        snake_Head.append(x1)
        snake_Head.append(y1)
        snake_List.append(snake_Head)
        if len(snake_List) > Length_of_snake:
            del snake_List[0]

        for x in snake_List[:-1]:
            if x == snake_Head:
                game_close = True

        our_snake(snake_block, snake_List)

        pygame.display.update()

        if x1 == foodx and y1 == foody:
            foodx = round(
                round(dis_width - snake_block) / 3.13 / snake_block) * snake_block
            foody = round(
                round(dis_height - snake_block) / 2.08 / snake_block) * snake_block
            Length_of_snake += 1

        clock.tick(snake_speed)

    pygame.quit()


gameLoop()

这是一个基本的贪吃蛇游戏代码，你可以通过运行它来体验贪吃蛇游戏。这段代码使用了 Pygame 库来实现游戏界面和游戏逻辑。

pythone二分查找

以下是两种Python实现二分查找算法的方法：

方法一：

def binary_search(arr, low, high, x):
    if high >= low:
        mid = (high + low) // 2
        if arr[mid] == x:
            return mid
        elif arr[mid] > x:
            return binary_search(arr, low, mid - 1, x)
        else:
            return binary_search(arr, mid + 1, high, x)
    else:
        return -1

arr = [1, 3, 6, 9, 10, 20, 30]
x = 10

result = binary_search(arr, 0, len(arr) - 1, x)

if result != -1:
    print("元素在数组中的索引为", str(result))
else:
    print("元素不在数组中")

方法二：

def binary_search(arr, x):
    low = 0
    high = len(arr) - 1
    mid = 0

    while low <= high:
        mid = (high + low) // 2

        if arr[mid] < x:
            low = mid + 1

        elif arr[mid] > x:
            high = mid - 1

        else:
            return mid

    return -1

arr = [1, 3, 6, 9, 10, 20, 30]
x = 10

result = binary_search(arr, x)

if result != -1:
    print("元素在数组中的索引为", str(result))
else:
    print("元素不在数组中")