%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %% Copyright: 2010 Integrated Sytems Laboratory, ETH Zurich %% http://www.iis.ee.ethz.ch/~sha3 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% function y = reduce(x) if x < 0 x = x; end; if x > 0 y = bitand(x, 255) - bitshift(x,-8); else y = mod(x,257); end