Labelling nodes for undirected graph

Question

Njud Alotaibi 2022-2-3

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1642100-labelling-nodes-for-undirected-graph

回答： ag 2023-9-29

I have the following issue in my code for L(2,1)-labelling problem. L(2,1)-labelling is to label positive integers to the nodes of graph such that

1) adjacent nodes receive value which differ by at least 2.

2) If the distance between the two nodes is 2 the difference between these nodes are 1.

my issue in the second loop

%this codes related to Njud Alotaibi (copy right)
function labellingcycles
%-----creating a graph-------
 s=[1 1 2 3 4];
 t=[2 3 4 5 5];
 G=graph(s,t);
 plot(G);
 %-----Sets--------
 S=[0,randperm(4)];
 Ver=[];
 x=[];
 % the first for loop here for first random labelling for the nodes 
    for i=1:5
       Ver(i)=S(i);
       Ver(:, i) = Ver(i);
    end
     Ver = Ver(:, 1:5) 
     
  % the second for loop to test the values in Ver set does it meet the  L(2,1)-labelling problem or not and 
  % store it in x set  
     for j=1:5
         % If conditions on the values should differen from their neighbors values and %
         % the difference between values should be 2 or more  
         if (Ver(j)~= Ver(neighbors(G,j)))  & (abs(Ver(j)-Ver(neighbors(G,j)))>=2) 
             x(j)=Ver(j);
             x(:, j) = x(j); 
             % if does not meet the condition i need to change the value to
             % meet the condition but how 
         else
             break % break becuse i just need to change the value that does not meet the condition 
             end 
         end 
     x = x(:, 1:5)
end