You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: mydijkstra.m
    path of file: ./repos/Mathematical_Modeling/Mathematical_Modeling_Algorithms_and_Applications_Second_Edition_Procedures_and_Data/04第4章
    
    the code of the file until where you have to start completion: function [mydistance,mypath]=mydijkstra(a,sb,db);
% 输入：a―邻接矩阵，a（i，j)是指i到j之间的距离，可以是有向的
% sb―起点的标号, db―终点的标号

    
function [mydistance,mypath]=mydijkstra(a,sb,db);
% 输入：a―邻接矩阵，a（i，j)是指i到j之间的距离，可以是有向的
% sb―起点的标号, db―终点的标号
% 输出：mydistance―最短路的距离, mypath―最短路的路径
n=size(a,1); visited(1:n) = 0;
distance(1:n) = inf; distance(sb) = 0; %起点到各顶点距离的初始化
visited(sb)=1; u=sb;  %u为最新的P标号顶点
parent(1:n) = 0; %前驱顶点的初始化
for i = 1: n-1
     id=find(visited==0); %查找未标号的顶点
     for v = id           
         if  a(u, v) + distance(u) < distance(v)
             distance(v) = distance(u) + a(u, v);  %修改标号值 
             parent(v) = u;                                    
         end