import java.util.Scanner; import java.util.ArrayList; import java.util.Arrays; import java.util.Collections; class Main { public static void main(String[] args) { Scanner in = new Scanner(System.in); String a = in.next(); String b = in.next(); boolean isA = false; boolean isB = false; for(int i=0; i<=12345; i++) { String str = String.valueOf(i); if(a.equals(str)) isA = true; if(b.equals(str)) isB = true; } if(isA && isB) System.out.println("OK"); else System.out.println("NO"); in.close(); } }