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#
# this is the code of exercise 4.12.2
#
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degblock := function( n, degne, dege, e, p )
 local dd, d1, d2, de, tup, x;
 dd:= []; d1:= ShallowCopy( degne ); d2 := ShallowCopy( dege );
 for x in [2..Length(d1)] do
   if d1[x] mod p <> d1[1] mod p then d1[x]:=-d1[x]; fi;
 od;
 for x in [2..Length(d2)] do
   if d2[x] mod p <> e  then d2[x]:= -d2[x]; fi;
 od;
 tup := UnorderedTuples(d1, e);;
 for x in tup do
   if Sum(x) in d2 then Add( dd , [x, Sum(x)] ); fi;
 od;
 for x in dd do Sort( x[1] ); od; dd:=Set(dd); Sort(dd);
 dd:=Filtered(dd, x -> Sum(List(x[1], a -> a^2)) + ((p-1)/e)*x[2]^2 < n);
 dd:=Filtered(dd, x -> Length(Positions(x,1)) = 1);
 return(dd);
end;;