AIMD algorithm charging value becoming signification

I am trying to this AIMD algorithm

for t=[1:1440] 
%generate uniform random number, p=rand 
if p < pi then 
ci(t+1) = b(1)ci(t) 
else 
ci(t+1) = b(2)ci(t) 
 endif 
    end else 
ci(t+1) = min(cimax,ci(t)+a detat) 
 endif 
 endfor 
 endwhile

as

    p=rand(1440,1);
for t=[1:1440];
 Cimax(t)=7;

    b1=p(1:1);
   b2=p(2:2);
  a=p(3:3);
   % generate uniform random number, 
   if p(t) > p(t+1)   
        ci(t+1) = b1*ci(t); 
   %elseif ci(t+1) = b2*Ci(t) 
   else    
        ci(t+1) = min(Cimax(t),ci(t)+a);

   end
 %  if V(t)<Vevent
  %     ci(t+1)=0
   %end
end  
end

but I can't seem to get a value of ci to increase towards 7 in the additive section or to decrease