def is_prime(num): if num==1: return False if num==2: return True for i in range(2,int(num**0.5)+1): if num%i==0: return False return True def reverse_num(num): return int(str(num)[::-1]) def find_absolute_primes(M,N): absolute_primes=[] for num in range(M,N+1): if is_prime(num) and is_prime(reverse_num(num)): absolute_primes.append(num) return absolute_primes M,N=map(int,input().split()) absolute_primes=find_absolute_primes(M,N) if absolute_primes: print(",".join(map(str,absolute_primes))) else: print("No")