带邻接矩阵的julia中的prim算法

function prim(adj_matrix)
    num_vertices = size(adj_matrix, 1)
    selected = zeros(Bool, num_vertices)  # 记录顶点是否已被选择
    selected[1] = true  # 选择起始顶点
    min_span_tree = zeros(Int, num_vertices-1, 2)  # 存储最小生成树的边

    for _ in 1:num_vertices-1
        min_weight = Inf
        u, v = 0, 0

        for i in 1:num_vertices
            if selected[i]
                for j in 1:num_vertices
                    if !selected[j] && adj_matrix[i, j] < min_weight
                        min_weight = adj_matrix[i, j]
                        u, v = i, j
                    end
                end
            end
        end

        selected[v] = true
        min_span_tree[_,:] = [u, v]
    end

    return min_span_tree
end