% Matlab program generating the Markov chain for the game of ladder %

n=0; X(1) = 1;
while X(n+1)<5;
  n=n+1; U=rand;
  X(n) = (U < .5)*1 + (U > .5)*( X(n-1)+1 );
end;
n          % number of steps it takes to reach the top %
X          % the history of X until the game is over   %
plot(X);