import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Scanner;
public class Main {
public static void main(String[] args) throws Exception {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
String str;
while((str = reader.readLine()) != null){
System.out.println(checkIp(str));
}
reader.close();
}
private static String checkIp(String ip) {
String[] items = ip.split("\\.");
if(items.length != 4){
return "NO";
}
for(int i = 0; i < items.length; i++) {
if(items[i].length() == 0 || (items[i].length() > 1 && items[i].startsWith("0")) || !Character.isDigit(items[i].charAt(0))) {
return "NO";
}
try{
int item = Integer.parseInt(items[i]);
if(item < 0 || item > 255) {
return "NO";
}
}catch(NumberFormatException e){
return "NO";
}
}
return "YES";
}
}