dz 123

var x,y,n,k:integer;
begin
writeln('Введите N>9');
readln(n);
k:=n div 7;
for y:=0 to k do
if (N-7*y) mod 3=0 then
begin
x:=(N-7*y) div 3;
writeln('x=',x,' y=',y);
end;
end.