code320A.cpp

/*
 * Contest : Codeforces
 * Problem : 320A - Magic Numbers
 * Link    : https://codeforces.com/contest/320/problem/A
 */

#include <bits/stdc++.h>
using namespace std;
using ll = long long;

#define fastio ios::sync_with_stdio(0); cin.tie(0);

bool solve(string str) {

  string aux = "";
  for (int i = 0; i < str.size(); i++) {
    if (str[i] != '1' && str[i] != '4') return false;

    aux += str[i];

    cerr << aux << endl;
    if (str[i] == '1') aux = "1";
    else if (aux == "4") return false;
    else if (aux == "14") continue;
    else if (aux == "144") aux.clear();
    else
      return false;
  }
  return true;
}

int main() {
  fastio

  string str;

  cin >> str;

  printf("%s\n", solve(str) ? "YES" : "NO");

  return 0;
}