\uc548\ub155\ud558\uc138\uc694, \ucf54\ub529\ud14c\uc2a4\ud2b8 \uc900\ube44\uc0dd \uc5ec\ub7ec\ubd84! \uc624\ub298\uc740 \uc18c\uc218(prime number)<\/strong>\uc640 \ud330\ub9b0\ub4dc\ub86c \uc218(palindrome number)<\/strong>\ub97c \ud65c\uc6a9\ud558\uc5ec \uc8fc\uc5b4\uc9c4 \ubc94\uc704\uc5d0\uc11c \ub450 \uc870\uac74\uc744 \ub3d9\uc2dc\uc5d0 \ub9cc\uc871\ud558\ub294 \uc218 \uc911 \ucd5c\uc19f\uac12\uc744 \ucc3e\ub294 \ubb38\uc81c\ub97c \ud480\uc5b4\ubcf4\uaca0\uc2b5\ub2c8\ub2e4. \uc774 \ubb38\uc81c\ub294 \uc54c\uace0\ub9ac\uc998 \ubb38\uc81c \ud480\uc774\uc5d0\uc11c \uc790\uc8fc \ub4f1\uc7a5\ud558\ub294 \uc8fc\uc81c \uc911 \ud558\ub098\ub85c, \ud6a8\uc728\uc801\uc778 \ucf54\ub4dc\ub97c \uc9dc\ub294 \ub370 \ub9ce\uc740 \ub3c4\uc6c0\uc774 \ub429\ub2c8\ub2e4. \uadf8\ub7fc \ubb38\uc81c\ub97c \ud568\uaed8 \uc0b4\ud3b4\ubcf4\uaca0\uc2b5\ub2c8\ub2e4.<\/p>\n \ub2e4\uc74c\uacfc \uac19\uc740 \uc870\uac74\uc744 \ub9cc\uc871\ud558\ub294 \ucd5c\uc19f\uac12\uc744 \ucc3e\ub294 \ud568\uc218\ub97c \uc791\uc131\ud558\uc138\uc694:<\/p>\n \uc608\ub97c \ub4e4\uc5b4, \ubb38\uc81c\ub97c \ud574\uacb0\ud558\uae30 \uc704\ud574 \ub2e4\uc74c\uacfc \uac19\uc740 \ub2e8\uacc4\ub85c \uc9c4\ud589\ud558\uaca0\uc2b5\ub2c8\ub2e4:<\/p>\n \uc18c\uc218\ub97c \ucc3e\uae30 \uc704\ud574 \uc5d0\ub77c\ud1a0\uc2a4\ud14c\ub124\uc2a4\uc758 \uccb4 \uc54c\uace0\ub9ac\uc998\uc744 \uc0ac\uc6a9\ud560 \uac83\uc785\ub2c8\ub2e4. \uc774 \uc54c\uace0\ub9ac\uc998\uc740 \ud6a8\uc728\uc801\uc73c\ub85c \uc18c\uc218\ub97c \ucc3e\ub294 \ubc29\ubc95 \uc911 \ud558\ub098\ub85c, \uc2dc\uac04 \ubcf5\uc7a1\ub3c4\uac00 \uc18c\uc218\ub97c \ucc3e\uc558\ub2e4\uba74, \uc774\uc81c \uc774\ub4e4 \uc911\uc5d0\uc11c \ud330\ub9b0\ub4dc\ub86c \uc218\ub97c \ucc3e\uc544\uc57c \ud569\ub2c8\ub2e4. \ud330\ub9b0\ub4dc\ub86c \uc218\ub294 \uc815\ubc29\ud5a5\uacfc \uc5ed\ubc29\ud5a5\uc774 \ub3d9\uc77c\ud55c \uc218\ub97c \uc758\ubbf8\ud569\ub2c8\ub2e4. \uc608\ub97c \ub4e4\uc5b4, \ub9c8\uc9c0\ub9c9\uc73c\ub85c, \ucc3e\uc740 \ud330\ub9b0\ub4dc\ub86c \uc218 \uc911\uc5d0\uc11c \ucd5c\uc19f\uac12\uc744 \ucc3e\uc544 \ubc18\ud658\ud558\ub294 \ud568\uc218\ub97c \uc791\uc131\ud569\ub2c8\ub2e4. \ucd5c\uc19f\uac12\uc744 \uc27d\uac8c \uad6c\ud558\uae30 \uc704\ud574 \uc704\uc758 \ubaa8\ub4e0 \ub2e8\uacc4\ub97c \uc885\ud569\ud558\uc600\uc744 \ub54c, \ucd5c\uc885 \ucf54\ub4dc\ub294 \ub2e4\uc74c\uacfc \uac19\uc2b5\ub2c8\ub2e4:<\/p>\n \uc774\ubc88 \uac15\uc88c\ub97c \ud1b5\ud574 \uc18c\uc218\uc640 \ud330\ub9b0\ub4dc\ub86c \uc218\uc758 \uac1c\ub150\uc744 \uc774\ud574\ud558\uace0, \uc774\ub97c \ud65c\uc6a9\ud558\uc5ec \ubb38\uc81c\ub97c \ud478\ub294 \ubc29\ubc95\uc744 \uc5f0\uc2b5\ud558\uc600\uc2b5\ub2c8\ub2e4. \uc18c\uc218\ub97c \ucc3e\ub294 \uc5d0\ub77c\ud1a0\uc2a4\ud14c\ub124\uc2a4\uc758 \uccb4\uc640 \uc22b\uc790\uac00 \ud330\ub9b0\ub4dc\ub86c\uc778\uc9c0 \ud655\uc778\ud558\ub294 \uac04\ub2e8\ud55c \uc54c\uace0\ub9ac\uc998\uc744 \ud1b5\ud574 \ud6a8\uc728\uc801\uc778 \ucf54\ub4dc\ub97c \uc791\uc131\ud560 \uc218 \uc788\uc5c8\uc2b5\ub2c8\ub2e4. \uc8fc\uc5b4\uc9c4 \ubb38\uc81c\ub97c \ud1b5\ud574 \uc54c\uace0\ub9ac\uc998\uc801 \uc0ac\uace0\uc640 \ucf54\ub529 \uc2e4\ub825\uc744 \ud55c \ub2e8\uacc4 \ubc1c\uc804\uc2dc\ud0a4\uae38 \ubc14\ub78d\ub2c8\ub2e4.<\/p>\n \ud5a5\ud6c4 \ub354\uc6b1 \ub2e4\uc591\ud55c \ubb38\uc81c\ub97c \ud568\uaed8 \ud480\uc5b4\ubcf4\uba70, \ucf54\ub529\ud14c\uc2a4\ud2b8 \uc900\ube44\uc5d0 \ud798\uc4f0\ub3c4\ub85d \ud574\uc694. \uac10\uc0ac\ud569\ub2c8\ub2e4!<\/p>\n <\/body><\/p>\n","protected":false},"excerpt":{"rendered":"\ubb38\uc81c \uc815\uc758<\/h2>\n
\n
N<\/code>\uc774 \uc785\ub825\uc73c\ub85c \uc8fc\uc5b4\uc9c8 \ub54c, 1 <= N <= 10,000<\/code>.<\/li>\nN<\/code> \uc774\ud558\uc758 \uc18c\uc218 \uc911\uc5d0\uc11c \ud330\ub9b0\ub4dc\ub86c\uc778 \uc218\ub97c \ucc3e\uc2b5\ub2c8\ub2e4.<\/li>\nN = 31<\/code>\uc778 \uacbd\uc6b0, \uc18c\uc218\ub294 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31<\/code>\uc774\uace0, \uc774 \uc911 \ud330\ub9b0\ub4dc\ub86c\uc778 \uc218\ub294 2, 3, 5, 7, 11<\/code>\uc785\ub2c8\ub2e4. \ub530\ub77c\uc11c 11<\/code>\uc774 \ucd5c\uc19f\uac12\uc774 \ub429\ub2c8\ub2e4.<\/p>\n\ubb38\uc81c\ub97c \ud478\ub294 \uacfc\uc815<\/h2>\n
\n
N<\/code> \uc774\ud558\uc758 \uc18c\uc218\ub97c \ucc3e\ub294 \ud568\uc218\ub97c \uc815\uc758\ud569\ub2c8\ub2e4.<\/li>\n1\ub2e8\uacc4: \uc18c\uc218 \ucc3e\uae30<\/h3>\n
O(n log log n)<\/code>\uc785\ub2c8\ub2e4. \uc774\ub97c \ud1b5\ud574 \uc8fc\uc5b4\uc9c4 N<\/code> \uc774\ud558\uc758 \ubaa8\ub4e0 \uc18c\uc218\ub97c \ucc3e\uc544\ub0bc \uc218 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n\uc5d0\ub77c\ud1a0\uc2a4\ud14c\ub124\uc2a4\uc758 \uccb4 \uc54c\uace0\ub9ac\uc998 \uad6c\ud604<\/h4>\n
def sieve_of_eratosthenes(n):\n primes = []\n is_prime = [True] * (n + 1)\n is_prime[0], is_prime[1] = False, False\n\n for i in range(2, int(n**0.5) + 1):\n if is_prime[i]:\n for j in range(i * i, n + 1, i):\n is_prime[j] = False\n\n for i in range(n + 1):\n if is_prime[i]:\n primes.append(i)\n\n return primes<\/code><\/pre>\n2\ub2e8\uacc4: \ud330\ub9b0\ub4dc\ub86c \uc218 \ud655\uc778\ud558\uae30<\/h3>\n
121<\/code>\uacfc 12321<\/code>\ub294 \ud330\ub9b0\ub4dc\ub86c\uc785\ub2c8\ub2e4. \uc774\ub97c \ud655\uc778\ud558\ub294 \ud568\uc218\ub294 \ub2e4\uc74c\uacfc \uac19\uc744 \uac83\uc785\ub2c8\ub2e4:<\/p>\ndef is_palindrome(num):\n return str(num) == str(num)[::-1]<\/code><\/pre>\n3\ub2e8\uacc4: \ucd5c\uc19f\uac12 \ubc18\ud658\ud558\uae30<\/h3>\n
min()<\/code> \ud568\uc218\ub97c \uc0ac\uc6a9\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\ndef find_smallest_palindrome_prime(n):\n primes = sieve_of_eratosthenes(n)\n palindrome_primes = [p for p in primes if is_palindrome(p)]\n \n if not palindrome_primes:\n return None # \ud330\ub9b0\ub4dc\ub86c \uc218\uac00 \uc5c6\uc744 \uacbd\uc6b0 None \ubc18\ud658\n return min(palindrome_primes)<\/code><\/pre>\n\uc804\uccb4 \ucf54\ub4dc<\/h2>\n
def sieve_of_eratosthenes(n):\n primes = []\n is_prime = [True] * (n + 1)\n is_prime[0], is_prime[1] = False, False\n\n for i in range(2, int(n**0.5) + 1):\n if is_prime[i]:\n for j in range(i * i, n + 1, i):\n is_prime[j] = False\n\n for i in range(n + 1):\n if is_prime[i]:\n primes.append(i)\n\n return primes\n\ndef is_palindrome(num):\n return str(num) == str(num)[::-1]\n\ndef find_smallest_palindrome_prime(n):\n primes = sieve_of_eratosthenes(n)\n palindrome_primes = [p for p in primes if is_palindrome(p)]\n \n if not palindrome_primes:\n return None \n return min(palindrome_primes)\n\n# \uc608\uc2dc \uc0ac\uc6a9\nN = 31\nresult = find_smallest_palindrome_prime(N)\nprint(f\"{N} \uc774\ud558\uc758 \uc18c\uc218 \uc911 \ud330\ub9b0\ub4dc\ub86c \uc218\uc758 \ucd5c\uc19f\uac12\uc740: {result}\")<\/code><\/pre>\n\uacb0\ub860<\/h2>\n