/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main(String[] args) {
    String str = "99.1";
    String regex = "(\\d{1,2}\\.\\d{1,2})|(\\d{1,2})";
    if (str.matches(regex)) {
        System.out.println("yes");
    } else {
        System.out.println("no");
    }
}
}