What am I doing wrong when returning the value from the function to my loop?

I have wriiten the program in c++ and verified that it works but am struggling with the loop part when converting it to MATLAB.

In c++ I have

while (int sent = dfs(s, t, INF))

but in MATLAB I do not know how to do this? Also for computing the paths from s->t in my dfs function I have the following if statment in c++

if (int sent = dfs (i, t, min (minimum, flow_capacity))) {
                // adjust the capacity
                Flow[s][i] += sent;
                Flow[i][s] -= sent;
                return sent;

How can I do this in MATLAB in where I have tried to implement the last parts but obviously have done so incorrectly? below is all my code.

Also I am aware that MATLAB has a built in function for these sorts of problems but I need to implement my own. Sorry if its something basic and trivial Im new to MATLAB.

Thanks in advance.

function ff
    clear;

%adjacency matrix representing capacities
 


    Cap =  [0, 4, 5, 0, 0, 0;
            0, 0, 2, 1, 4, 0;
            0, 0, 0, 0, 3, 0;
            0, 0, 0, 0, 0, 2;
            0, 0, 0, 2, 0, 6;
            0, 0, 0, 0, 0, 0;];
                            
    
% source and sink
 INF=999999;
 s = 1; 
 t = 6; 
 max_flow=0;
 len = length(Cap);

 sent = 0;

 Flow =zeros([len,len]);
 
 visited=boolean(zeros(1,len));
 
   %sent = dfs(s,t,INF);
    sent = dfs(s,t,INF);

   while  sent==dfs(s,t,INF);
      
       
       max_flow =+sent;

       visited=boolean(zeros(1,len));
      
   end
  
  disp('Residual graph:');
  disp(Flow);
  disp(['Max flow is ' num2str(max_flow)]);


%dfs

    function F = dfs(s,t,minimum)
      
   
     visited(s) = true;
     
       if s==t
          F = minimum;
        end 
 
       for i = 1:len
            flow_cap = Cap(s,i) - Flow(s,i);
            

            if ~visited(i) && flow_cap > 0
               
                  if sent == dfs(i,t,min(minimum,flow_cap))

                     Flow(s,i) = Flow(s,i)+sent;
                     Flow(i,s) = Flow(i,s)-sent ;
                      F=+sent;
                   end 
                    

            end 
            
       end
      
    end
    
    end

Answer 1

[Jan]

% C++:
% while (int sent = dfs(s, t, INF))

sent = dfs(s, t, INF);
while sent ~= 0
    sent = dfs(s, t, Inf);
end

And:

% if (int sent = dfs (i, t, min (minimum, flow_capacity))) {
%                 // adjust the capacity
%                 Flow[s][i] += sent;
%                 Flow[i][s] -= sent;
%                 return sent;

sent = dfs(i, t, min(minimum, flow_capacity));
if sent
    Flow(s,i) = Flow(s,i) + sent;
    Flow(i,s) = Flow(i,s) - sent;
end

Omit the useless "clear;"

Replace

 Flow =zeros([len,len]);
 visited=boolean(zeros(1,len));
 

by

 Flow = zeros(len, len);
 visited = false(1, len);

[Ryan O Malley]

Thanks very much, this helped me beyond messure!

I also didnt set the value of

F=0;

at the beginning of my dfs function incase anyone is looking to this question for help.