def is_prime(n): """检查一个数是否为素数。""" if n <= 1: return False if n <= 3: return True if n % 2 == 0 or n % 3 == 0: return False i = 5 while i * i <= n: if n % i == 0 or n % (i + 2) == 0: return False i += 6 return True def find_emirps(M, N): """寻找M和N之间的所有绝对素数。""" emirps = [] for num in range(M, N+1): if is_prime(num): reversed_num = int(str(num)[::-1]) if num != reversed_num and is_prime(reversed_num): emirps.append(num) return emirps # 读取输入 M, N = map(int, input().split()) # 寻找绝对素数 emirps = find_emirps(M, N) # 输出结果 if emirps: print(','.join(map(str, emirps))) else: print('No')