var a,b,c,p:integer;
begin
write('nhap chu vi: '); readln(p);
if b>2 then begin
writeln('do dai 3 canh cua tam giac co the la: ');
for a:=1 to p do
for b:=a to p do
for c:=b to p do
if (a+b+c=p) and (a+b>c) and (b+c>a) and (a+c>b) then
writeln(a,' ',b,' ',c);
end else write('khong co tam giac thoa man');
readln
end.