CF320A.Magic Numbers

传统题 时间 2000 ms 内存 256 MiB 4 尝试 1 已通过 1 标签

Magic Numbers

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

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

Output

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

Samples

114114
YES
1111
YES
441231
NO

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