2480.Magic Numbers

Time Limit: 1s Memory Limit: 256MB

A magic number is a number formed by concatenation of numbers 1, 14 and 144. We can use each of these numbers any number of times. Therefore 14144, 141414 and 1411 are magic numbers but 1444, 514 and 414 are not.

You're given a number. Determine if it is a magic number or not.

Input Format(From the terminal/stdin)

The first line of input contains an integer n, (1 \le n \le 109). This number doesn't contain leading zeros.

Output Format(To the terminal/stdout)

Print "YES" if n is a magic number or print "NO" if it's not.

Sample Input 1

Copy 
114114
      \n

Sample Output 1

Copy 
YES
   \n

Sample Input 2

Copy 
1111
    \n

Sample Output 2

Copy 
YES
   \n

Sample Input 3

Copy 
441231
      \n

Sample Output 3

Copy 
NO
  \n

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