Help. Why does my matlab code work one moment, and then suddenly stops working?

It just suddenly keeps runnning forever. Please help.

%%Initial Populations
%%------------------------------------------------
%Path Selection

clear start_node end_node Dist Fit
fprintf('Enter Integer Only');
start_node=input('Start Node: ');
end_node=input('End Node: ');
dist = zeros(49,49);

%import distance values from excel
for i = 1:168
    dist(Node1(i,1), Node2(i,1)) = Distance(i,1);
end

clear path;
n=2;
path(1,1)=start_node;
start=start_node;
dist1=dist;
total_dist=0;
%o=0;
%r=0 might not need
while start ~= end_node
    clear store_value chosen;
    k=1;

      %possible next node number
      for j=1:49
          if dist1(start,j) > 0
              store_value(k)=j;
              k=k+1;
          end
      end

      %random choosing for next node number
      idx = randperm(numel(store_value));
      chosen = store_value(idx(1));

      %Should never have this situaiton since 2D analysis only
      %if chosen - start == 25 & r==0;
       %   r=1;
      %elseif chosen - start == 25 && r==1
       %   while chosen - start == 25
        %      idx=randperm(numel(store_value));
         %     chosen = store_value(idx(1));
         % end
          %r=0;
     % end

      %Path
      path(1,n) = chosen;
      n=n+1;
      start = chosen;
  end
  %End of Path Selection
  %%Path Elimination
  %---------------------------------------------------
  a = numel(unique(path));
  b = numel(path);
  path1 = path;

while numel(path) ~= numel(unique(path))
    h=0;
    x=numel(path);

    for h=1:x
        if h<x-2 && path(1,h) == path(1,h+2)
            path([h+1,h+2]) = [];
            x=numel(path);

        elseif h == x-1 || h == x
            break;
        end;
        x=numel(path);
    end
      k = 1;
      for j = 1:x
          if j < x-2 && path(1,j) == path(1,j+2)
              k = k+1;
          end
      end
      if k == 1;
          break;
     end
  end

path3 = path;

while true
   pathhist = histcounts(path3, [unique(path3), Inf]); 
   duplicate = path3(find(pathhist > 1, 1)); %find identical digit
   if isempty(duplicate)
      break; %nothing left to remove, exit loop
   end
   occurences = path3 == duplicate;
   path3(find(occurences, 1) : find(occurences, 1, 'last')-1) = []; %delete 1st occurence and anything up to last occurence
end

Answer 1

[Image Analyst]

I guess you entered something that caused an infinite loop. What inputs did you provide it?

And read this to fix your formatting.

[Xi Wen Lim]

Sorry I don't really understand what you mean. The entire code script is above. Um. I entered 1 for start_node and 49 for end_node. And imported some values from excel over into matlab.

[Image Analyst]

It says it doesn't know what Distance is. If you still need help, post the code and workbook to get the Distance values into your program so I can run it.