Răspuns:
var x, y, z : integer;
begin
write('Introduceti valorile celor trei numere x, y, z: ');readln(x,y,z);
if (x=pred(y)) and (y=pred(z)) then writeln('Sunt consecutive in multimea N')
else if (x=succ(y)) and (y=succ(z)) then writeln('Sunt consecutive in multimea N')
else writeln('Nu sunt consecutive in multimea N');
end.