  To simulate the interaction of cosmic rays with the Earth atmosphere requires
highly complex computational resources and several statistical techniques have
been developed to simplify those calculations. It is common to implement the
thinning algorithms to reduce the number of secondary particles by assigning
weights to representative particles in the evolution of the cascade. However,
since this is a compression method with information loss, it is required to
recover the original flux of secondary particles without introduce artificial
biases. In this work we present the preliminary results of our version of the
de-thinning algorithm for the reconstruction of thinned simulations of
extensive air showers initiated by cosmic rays and photons in the energy range
$10^{15} < E/\mathrm{eV} < 10^{17}$.
