Program UCLN;
Uses crt;
Var a,b,r:byte;
Begin
Clrscr;
Writeln('CHUONG TRINH TIM UCLN CUA HAI SO');
Write('Nhap a: ');readln(a);
Write('Nhap b: ');readln(b);
r:=a mod b;
While r<> 0 do
Begin
b:=r;
a:=b;
r:=a mod b;
End;
Write('UCLN cua hai so la: ',b);
Readln
End.