uses crt;
var a,b,ucln,x,y:integer;
begin
clrscr;
write('nhap a='); readln(a);
write('nhap b='); readln(b);
x:=a;
y:=b;
while a<>b do
begin
if a>b then a:=a-b
else b:=b-a;
end;
ucln:=a;
if ucln=1 then writeln(x,' va ',y,' la hai so nguyen to cung nhau')
else writeln(x,' va ',y,' khong phai la hai so nguyen to cung nhau');
readln;
end.