function nbr_slp=T1_event(N_f,NN_i)
% Extracts the cells that undergo neighbor slipping, 'nbr_slp', given the initial
% next-nearest neighbors, 'NN_i', and final nearest neighbors, 'N_f'
% nbr-slp - cell array listing cells that undergo neighbor slipping.
%
%For bugs, comments, etc. please contact Kapil Krishan :
%kkrishan@uci.edu
%www.physics.uci.edu/~foams
%version: I

for ic=1:size(N_f,1)
    nbr_slp{ic}=find(NN_i(ic,:).*N_f(ic,:)==1);
end