Concatenated Prime Check

You are given two integers a and b. Your task is to concatenate these two integers (i.e. by writing their digits side by side) to form a new integer, and then determine whether this new integer is a prime number.

A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself. In other words, a number \( p \) is prime if \( p > 1 \) and \( \forall d \in \mathbb{N},\ d\mid p \Rightarrow (d = 1 \text{ or } d = p) \).

If the concatenated number is prime, print YES; otherwise, print NO.

inputFormat

The input is read from standard input (STDIN) and consists of two integers, a and b, separated by whitespace.

outputFormat

The output should be written to standard output (STDOUT) and consist of a single line containing YES if the integer formed by concatenating a and b is prime, or NO otherwise.

7 13

NO