设计一个数据结构实验代码，要求：1. 熟练掌握图的两种存储方式：邻接矩阵和邻接表。 2. 通过领接表统计图中顶点度为n的顶点数量。 3. 通过邻接矩阵实现最小生成树的prime算法。

邻接矩阵实现最小生成树的prime算法代码：

def prim(graph):
    # 初始化
    n = len(graph)
    visited = [False] * n
    dist = [float('inf')] * n
    parent = [-1] * n
    dist[0] = 0

    # 选择n-1次最小边
    for _ in range(n-1):
        # 找到当前未访问的最小距离的点
        u = min_distance(dist, visited)
        visited[u] = True

        # 更新与该点相邻的点的距离
        for v in range(n):
            if graph[u][v] and not visited[v] and graph[u][v] < dist[v]:
                dist[v] = graph[u][v]
                parent[v] = u

    # 构建最小生成树
    mst = []
    for i in range(1, n):
        mst.append((parent[i], i, graph[parent[i]][i]))

    return mst

def min_distance(dist, visited):
    min_dist = float('inf')
    min_index = -1
    for i in range(len(dist)):
        if not visited[i] and dist[i] < min_dist:
            min_dist = dist[i]
            min_index = i
    return min_index

邻接表统计图中顶点度为n的顶点数量的代码：

def degree_count(adj_list, n):
    count = 0
    for i in range(len(adj_list)):
        if len(adj_list[i]) == n:
            count += 1
    return count