\begin{array}{c} \color{#db1616}{\texttt{#Khoadang09}} \end{array}
`@`$\texttt{Ruby: }$

def prime(n)
    return false if n < 2 
    return true if n == 2 || n == 3
    return false if n % 2 == 0 || n % 3 == 0
    i = 5
    while i <= n
        return false if n % i == 0 || n % (i + 2) == 0
        i += 6 
    end
end
a, b = gets.chomp.split.map(&:to_i)
puts prime(a) && prime(b) ? "YES" : "NO"