Lab5v12

function [ r ] = lab4( A )
%LAB4 counts elements between first and last positive
%in the single-dimensional array A
N=length(A);
kf=-1; %index of the first positive element
kl=-1; %index of the  last positive element

k=1; %loop counter
while (k<=N) && (kf==-1)
  if A(k)>0
      kf=k;
  end
  k=k+1;
end

k=N; %downwards
while (k>=1) && (kl==-1)
  if A(k)>0
      kl=k;
  end
  k=k-1;
end

if (kf==-1) && (kl==-1)
    warning('No positive elements!')
end
r=kl-kf-1;
end