Code including multiply embedded for loops with conditions

Hello, i have a signal (nfo) and having found its peaks (pks) and minima (val) i should do the following : If it starts with peak (R0), then for the next peak (R1) if the next minima (K2) < previous (K1) then delete previous(K1,R1) , else delete next(R1,K2) , see the attached photo for better explanation. I have done some code but i get confused in the part than i compare with the previous (K1,R1) , here is my code

   for kk=2:length(pks)-1 
      if pks(kk)<pks(kk+1)
         tpks(kk)=pks(kk+1); 
         tl1(kk)=l1(kk+1);
       end
   end
    tpks=tpks(tpks~=0);
    tl1=tl1(tl1~=0);

If my signal starts with minima well the idea is similar (see photo).

Note pks are the peaks data, l1 the location of the peaks , val the minima and l2 the locations of minima. Any help appreciated thanks in advance.