w=[0 2 1 8 inf inf inf inf;2 0 inf 6 1 inf inf inf;1 inf 0 7 inf inf 9 inf;...
      8 6 7 0 5 1 2 inf;inf 1 inf 5 0 3 inf 9;inf inf inf 1 3 0 4 6;...
      inf inf 9 2 inf 4 0 3;inf inf inf inf 9 6 3 0]
   n=size(w,1);
   w1=w(1,:);
   
   %賦初值
   for i=1:n
      l(i)=w1(i);
      z(i)=1;
   end
   s=[];
   s(1)=1;
   u=s(1);
   k=1
   l
   z
   

while k<n
   % 更新 l(v) 和 z(v)
   for i=1:n
      for j=1:k
      if i~=s(j) 
         if l(i)>l(u)+w(u,i)
            l(i)=l(u)+w(u,i);
            z(i)=u;
         end
      end
      end
   end
   l
   z
   
   %求v*
   ll=l;
   for i=1:n
      for j=1:k
         if i~=s(j)
            ll(i)=ll(i);
         else 
            ll(i)=inf;
         end
      end
   end
   
   lv=inf;
   for i=1:n
      if ll(i)<lv
         lv=ll(i);
         v=i;
      end
   end     
   lv
   v
   
  s(k+1)=v
  k=k+1
  u=s(k)
  
end
l
z