用python解决一笔画问题的程序代码

下面是使用深度优先搜索算法来解决一笔画问题的Python代码：

def dfs(graph, v, visited):
    visited[v] = True
    for i in graph[v]:
        if not visited[i]:
            dfs(graph, i, visited)

def can_draw(graph):
    n = len(graph)
    visited = [False] * n
    dfs(graph, 0, visited)
    return all(visited)

def is_eulerian(graph):
    n = len(graph)
    degree = [0] * n
    for i in range(n):
        degree[i] = len(graph[i])
    odd_degree_count = sum(1 for x in degree if x % 2 == 1)
    return odd_degree_count == 0 or odd_degree_count == 2

def one_stroke_drawing(graph):
    if not is_eulerian(graph):
        return False
    if not can_draw(graph):
        return False
    return True

其中，`dfs`函数用于遍历连通图，`can_draw`函数用于判断图是否连通，`is_eulerian`函数用于判断图是否存在欧拉回路或欧拉路径。最后的`one_stroke_drawing`函数即为解决一笔画问题的函数，返回值为`True`表示可以用一笔画完成，否则返回`False`。