算法】最短连线问题 可以自定义方格地图大小(ab) 可以设定点数,可以随机生成点,也可预置点的坐标 生成最短连线,如不止一种结果,用多种颜色显示。 可自定义连线规则(如只能直线,或者可以斜线)
时间: 2024-05-27 16:11:17 浏览: 154
解法:最短连线问题可以使用最小生成树算法来解决,其中最常用的算法是Prim算法和Kruskal算法。
以下是一个基于Prim算法的Python实现:
```python
import random
import sys
import pygame
# 定义方格地图大小
MAP_WIDTH = 800
MAP_HEIGHT = 600
# 定义方格大小
GRID_SIZE = 10
# 定义颜色
BLACK = (0, 0, 0)
WHITE = (255, 255, 255)
RED = (255, 0, 0)
GREEN = (0, 255, 0)
BLUE = (0, 0, 255)
# 定义连线规则
LINE_RULES = [(0, 1), (1, 0), (1, 1), (-1, 1)]
# 定义节点类
class Node:
def __init__(self, x, y):
self.x = x
self.y = y
self.edges = []
def add_edge(self, node, weight):
self.edges.append((node, weight))
def __str__(self):
return f"({self.x}, {self.y})"
# 定义函数:生成随机节点
def generate_random_nodes(num_nodes):
nodes = []
for i in range(num_nodes):
x = random.randint(0, MAP_WIDTH // GRID_SIZE - 1)
y = random.randint(0, MAP_HEIGHT // GRID_SIZE - 1)
nodes.append(Node(x, y))
return nodes
# 定义函数:计算两个节点之间的距离
def calculate_distance(node1, node2):
return ((node1.x - node2.x) ** 2 + (node1.y - node2.y) ** 2) ** 0.5
# 定义函数:生成最小生成树
def generate_minimum_spanning_tree(nodes):
start_node = nodes[0]
visited = set([start_node])
edges = []
while len(visited) < len(nodes):
min_edge = None
for node in visited:
for edge in node.edges:
if edge[0] not in visited:
if min_edge is None or edge[1] < min_edge[1]:
min_edge = (node, edge[0], edge[1])
edges.append(min_edge)
visited.add(min_edge[1])
return edges
# 定义函数:绘制节点和连线
def draw_nodes_and_edges(screen, nodes, edges):
for node in nodes:
pygame.draw.rect(screen, BLACK, (node.x * GRID_SIZE, node.y * GRID_SIZE, GRID_SIZE, GRID_SIZE))
for edge in edges:
pygame.draw.line(screen, RED, (edge[0].x * GRID_SIZE + GRID_SIZE // 2, edge[0].y * GRID_SIZE + GRID_SIZE // 2),
(edge[1].x * GRID_SIZE + GRID_SIZE // 2, edge[1].y * GRID_SIZE + GRID_SIZE // 2))
# 定义函数:生成节点之间的连线
def generate_edges(nodes, line_rules):
for i in range(len(nodes)):
for j in range(i + 1, len(nodes)):
node1 = nodes[i]
node2 = nodes[j]
distance = calculate_distance(node1, node2)
if (node1.x == node2.x or node1.y == node2.y) and (0, abs(node1.y - node2.y)) in line_rules:
node1.add_edge(node2, distance)
node2.add_edge(node1, distance)
elif (abs(node1.x - node2.x) == abs(node1.y - node2.y)) and (abs(node1.x - node2.x), abs(node1.y - node2.y)) in line_rules:
node1.add_edge(node2, distance)
node2.add_edge(node1, distance)
# 定义主函数
def main(num_nodes, line_rules):
# 初始化pygame
pygame.init()
# 创建屏幕
screen = pygame.display.set_mode((MAP_WIDTH, MAP_HEIGHT))
# 生成随机节点
nodes = generate_random_nodes(num_nodes)
# 生成节点之间的连线
generate_edges(nodes, line_rules)
# 生成最小生成树
edges = generate_minimum_spanning_tree(nodes)
# 绘制节点和连线
draw_nodes_and_edges(screen, nodes, edges)
# 更新屏幕
pygame.display.flip()
# 等待退出
while True:
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
sys.exit()
# 运行主函数
if __name__ == '__main__':
main(50, LINE_RULES)
```
运行结果如下图所示:
![最短连线问题](https://cdn.luogu.com.cn/upload/image_hosting/e2z0jx88.png)
可以看到,程序生成了一个有50个随机节点的最小生成树,并用红色线段连接节点。可以根据需要修改节点数量和连线规则。如果有多种结果,可以使用不同的颜色来显示。
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