#!/usr/bin/perl -i

while (<>) {
  /:extrafuns.*DIST_ZERO/ and next;
  s/\(and (\(= \S+ \(\+ DIST_ZERO_\d+ \d+\)\))/(distinct $1/g;
  s/\(= (\S+) \(\+ DIST_ZERO_\d+ \d+\)\)/$1/g;
  print;
}