Test directed graph for cycles, write them, and change paths to it become acyclic

Hi, I'm totally new to matlab, I need to write an algorithm where directed graph would be tested for cycles, cycles writed down and then their paths directions changed so that the graph becomes acyclic.

Here is my code so far..

clear all
clc

%  Number of edges
n = input ('Kiek grafe virsuniu:');

%  Create graph
A = round(rand(n));
no_el = n*n; % elementu sk.
dlg = 1:n+1:no_el; % isrinkti pagrindine istrizaine
A(dlg) = 0; % pagrindines istrizaines skaicius paversti nuluikais

testi_viska = 1;
testi = 1;

KelioIlgis = 1;
i = 1;
j = 1;

while i <= n && testi_viska == 1

      %KelioIlgis = (KelioIlgis + 1);
      Kelias(1,j) = i;
      testi = 1;
      j = 1;

      while j <= n && testi == 1

          if A(i,j) == 1
              KelioIlgis = (KelioIlgis + 1);
              Kelias(1, KelioIlgis) = j;

                  c = 1;

                  while c < KelioIlgis
                      if Kelias(1,c)==Kelias(1,KelioIlgis);
                          disp('CIKLAS!');
                          disp(Kelias);
                          A(i,j) = 0;
                          %A(j,i) = 1;
                          Kelias = Kelias - Kelias(1,KelioIlgis);
                          KelioIlgis = (KelioIlgis - 1);
                          testi = 1;
                      elseif Kelias(1,c)~=Kelias(1,KelioIlgis);
                          disp('CIKLO NĖRA'); 
                          testi = 0;
                          i = j;
                          c = c + 1;
                      end
                  end

          end;

      end;
  end;

It looks like somewhere it becomes endless... Guys please help me out!

[Walter Roberson]

Does it display anything endlessly? Have you tried stepping through with the debugger?