uses crt; var n,k:longint; c:real; function gt(a:longint):longint; var i:longint; begin gt:=1; for i:=1 to a do gt:=gt*i; end; begin clrscr; write('Nhap k: ');readln(k); write('Nhap n: ');readln(n); c:=gt(k)*gt(n)/gt(n-k); writeln('C= ',c:0:5); readln end.